Sneaking Up On The Criegee Intermediate From Below: Predicted Photoelectron Spectrum Of The CH_2OO^- Anion And W3-F12 Electron Affinity Of CH_2OO
SSneaking Up On The Criegee Intermediate FromBelow: Predicted Photoelectron Spectrum Of TheCH OO – Anion And W3-F12 Electron Affinity OfCH OO A. Karton M. Kettner D. A. Wild ∗ School of Chemistry and BiochemistryThe University of Western AustraliaM310, 35 Stirling Hwy, Crawley, Australia 6009 [email protected]
High level ab initio calculations were undertaken on the CH OO anionand neutral species to predict the electron affinity and anion photoelec-tron spectrum. The electron affinity of CH OO, . eV, and barrierheight for dissociation of CH OO – to O – and CH O, . kJ mol − , areobtained by means of the W3-F12 thermochemical protocol. Two majorgeometric differences between the anion and neutral, being the dihedralangle of the terminal hydrogen atoms with respect to C − O − O plane,and the O − O bond length, are reflected in the predicted spectrum aspronounced vibrational progressions. ∗ Author to whom correspondence should be addressed. a r X i v : . [ phy s i c s . c h e m - ph ] S e p Introduction
Elucidation of the properties and reaction pathways of Criegee intermediates has gainedfresh momentum recently. These intermediates, first proposed by Criegee in 1949, areof importance in the ozonolysis and breakdown of unsaturated hydrocarbons, whichhas been shown to be a major pathway in the troposphere leading to OH radicals andparticulate matter. The simplest Criegee intermediate is CH OO and has in previouswork been named formaldehyde oxide, peroxymethylene, or more generally as a carbonyloxide.The reason for the renewed activity can be attributed to a breakthrough by Taatjesand co-workers who developed novel gas-phase synthetic techniques for the Criegee in-termediates. They first used the chlorine atom initiated reaction with DMSO, followedby photolysis to form CH OO, and shortly after a second route was developed wherebythey photolysed CH I in the presence of O . In this second study, the authors deter-mined rates of reaction between the Criegee intermediate and atmospherically importantspecies NO, NO , SO , and H O. The group has recently extended their initial study tothe next largest Criegee intermediate, namely CH CHOO. Since the breakthrough of this new synthetic approach there has been a burst ofactivity to characterise the Criegee intermediate by gas-phase IR spectroscopy in the cm − to cm − region and determination of the UV absorption cross section andphotochemistry. The infrared spectrum was interpreted with the aid of ab initio cal-culations where three other possible structures for CH O were computed, dioxirane,methylenebis(oxy) (also known as dioxymethane), and formic acid, and compared withthe experimental spectrum.Clearly the best match between experiment and theory was with the Criegee interme-diate, thereby providing definitive proof of its synthesis. Lester and co-workers reportedthe UV absorption of the CH OO biradical in the nm to nm region, assigned tothe B ← X transition, where the excited state (B) is purely repulsive along the O − Ocoordinate. Results from this work are extremely useful, as they identified the signatureof the Criegee intermediate that can be applied in future laboratory or field studies.The Criegee intermediates have received quite a deal of theoretical attention overthe years, with the state of play well represented in References [11], [12] and [13] andreferences cited therein. Fang et al. studied the potential energy surface of the reactionof CH and O on the singlet and triplet surfaces using CASSCF-type S calculations. Nguyen et al. obtained the heat of formation and ionisation energy of the Criegeeintermediate at the CCSD(T)/CBS level using W1 theory. It is worthwhile noting thatquite recently, Dyke and co-workers used TDDFT, EOM-CCSD, and CASSCF methodsto investigate the first few excited electronic states of the simplest CH OO intermediate. They also predicted the form of the photoelectron spectrum, i.e. cation ← neutraltransitions.In this contribution, evidence for the stability of the CH OO – anion from high levelW3-F12 calculations is provided. The anion is stable with respect to both autodetach-ment to the CH OO neutral and unimolecular dissociation to CH O (formaldehyde) andO – products. We believe that it will be possible to characterise the neutral CH OO,and possibly larger, Criegee intermediates through anion photoelectron spectroscopy; avaluable method for mapping out the vibrational and electronic states of neutral species.These experiments are appealing as mass spectrometry can be used to isolate the targetcomplex out of an ion population prior to spectroscopic interrogation. There has been2 large volume of work produced in this area from the groups of Lineberger, Neumark,Bowen, Wang, and Kaya, and Johnson with some representative examples provided inreferences [16–21]. Our laboratory has also recently made contributions in this area.
To the best of the authors’ knowledge, there have been no previous computationalor experimental investigations of the CH OO – anion. A computational study by Roosand co-workers deals with the dioxyrane, dioxymethane, and the dioxymethane anion, however the dioxymethane species have both oxygen atoms bound to carbon and notto each other, while for dioxyrane there is an O − O bond. There has been experimen-tal work undertaken on very similar species, namely the alkyl peroxides CH OO – andCH CH OO – . Blanksby et al. produced negative ion photoelectron spectra and deter-mined the adiabatic electron affinities of CH OO and CH CH OO to be . eV and . eV respectively. The spectrum of the CH OO – anion showed resolved vibra-tional progressions in the O − O stretching and H C − O − O bending modes. The spectrumof the CH CH OO – also showed well resolved vibrational progressions. Assignment ofone progression to the O − O stretch was clear, while a second progression was assignedto a bending mode; however, it was unclear whether it was the C − C − O or C − O − Omode as these modes are predicted to lie very close in frequency. With regard to thealkyl peroxy systems it would be remiss not to make reference to the work undertakenby Xu et al. They performed an extensive computational study on the R − OO andR − OO – anion species with R = CH , C H , n -C H , n -C H , n -C H , i -C H , and t -C H . They predicted the structures, vibrational frequencies, and electron affinities ofthe neutral species using seven different density functional or hybrid density functionalmethods.In the present Letter we obtain the heat of formation and electron affinity of the Criegeeintermediate using the recently developed W3-F12 theory. W3-F12 represents a layeredextrapolation to the relativistic, all-electron CCSDT(Q)/CBS energy (complete basis setlimit coupled cluster with singles, doubles, triples, and quasiperturbative quadruple exci-tations) and shows excellent performance for systems containing first-row elements (andH). Specifically, over the first-row systems in the W4-11 dataset, W3-F12 attains aroot mean square deviation (RMSD) of only . kJ mol − against all-electron, relativisticreference atomisation energies obtained close to the full configuration interaction (FCI)infinite basis set limit. In addition to the heats of formation and electron affinity of theCH OO species, we obtain the barrier height and energy for the CH OO – CH O + O – reaction using W3-F12 theory. The geometries and harmonic frequencies of the anion and neutral CH OO species wereobtained at the CCSD(T)/A (cid:48)
VQZ level of theory (where A (cid:48) V n Z indicates the combina-tion of Dunning’s aug-cc-pV n Z basis set on carbon and oxygen and the standard cc-pV n Zbasis set on hydrogen).
The geometry and harmonic frequencies for the transitionstructure of the CH OO – CH O + O – reaction are obtained at the CCSD(T)/A (cid:48) VTZlevel of theory. The optimized geometries for all the species considered in the presentwork are given as Cartesian coordinate form in Table S1 of the supporting information.All the high-level ab initio calculations were performed using the
Molpro programsuite, while all the density functional theory (DFT) calculations were carried out withthe Gaussian
09 program suite. e ) of the CH OO andCH OO – species are obtained by means of the W3-F12 procedure. W3-F12 theorycombines F12 methods with extrapolation techniques in order to reproduce theCCSDT(Q) basis set limit energy. The CCSD(T)/CBS energy is obtained from theW2-F12 theory and the post-CCSD(T) contributions are obtained from W3.2 theory. In brief, the Hartree–Fock component is calculated with the VQZ-F12 basis set (V n Z-F12denotes the cc-pV n Z-F12 basis sets of Peterson et al. which were developed for explicitlycorrelated calculations). Note that the complementary auxiliary basis (CABS) singlescorrection is included in the SCF energy.
The valence CCSD-F12 correlation energyis extrapolated from the VTZ-F12 and VQZ-F12 basis sets, using the E ( L ) = E ∞ + A/L α two-point extrapolation formula, with α = . . In all of the explicitly-correlated coupledcluster calculations the diagonal, fixed-amplitude 3C(FIX) ansatz and the CCSD-F12b approximation are employed. The quasiperturbative triples, (T), correctionsare obtained from standard CCSD(T) calculations (i.e., without inclusion of F12 terms)and scaled by the factor f = 0 . · E MP2 − F12 /E MP2 . This approach has been shownto accelerate the basis set convergence.
The higher-order connected triples, T -(T),valence correlation contribution is extrapolated from the cc-pVDZ and cc-pVTZ basissets using the above two-point extrapolation formula with α = 3, and the parentheti-cal connected quadruples contribution (CCSDT(Q)–CCSDT) is calculated with the cc-pVDZ basis set. The CCSD inner-shell contribution is calculated with the core-valenceweighted correlation-consistent A (cid:48)
PWCVTZ basis set of Peterson and Dunning, whilstthe (T) inner-shell contribution is calculated with the PWCVTZ(no f ) basis set (whereA (cid:48) PWCVTZ indicates the combination of the cc-pVTZ basis set on hydrogen and the aug-cc-pwCVTZ basis set on carbon, and PWCVTZ(no f ) indicates the cc-pwCVTZ basis setwithout the f functions). The scalar relativistic contribution (in the second-order Dou-glas–Kroll–Hess approximation ) is obtained as the difference between non-relativisticCCSD(T)/A (cid:48)
VDZ and relativistic CCSD(T)/A (cid:48)
VDZ-DK calculations (where A (cid:48)
VDZ-DKindicates the combination of the cc-pVDZ-DK basis set on H and aug-cc-pVDZ-DK basisset on C and O). The atomic spin-orbit coupling terms are taken from the experimentalfine structure, and the diagonal Born–Oppenheimer corrections (DBOC) are calculatedat the HF/A (cid:48)
VTZ level of theory. The zero-point vibrational energies (ZPVEs) are de-rived from the harmonic frequencies (calculated at the CCSD(T)/A (cid:48)
VQZ level of theoryfor the CH OO and CH OO – species, and the CCSD(T)/A (cid:48) VTZ level of theory for theCH O · · · O – transition structure).The total atomisation energies at K (TAE ) are converted to a heats of formationat K using the Active Thermochemical Tables (ATcT) atomic heats of forma-tion at K (H . kJ mol − , C . kJ mol − , and O . kJ mol − ),and the CODATA enthalpy functions, H − H , for the elemental reference states(H (g) = . kJ mol − and C( cr ,graphite) = . kJ mol − ), while the en-thalpy functions for the CH OO and CH OO – species are obtained within the ridgedrotor harmonic oscillator (RRHO) approximation from B3LYP/A (cid:48) VTZ geometries andharmonic frequencies.
Anion photoelectron spectra were simulated by determiningthe Franck–Condon Factors (FCFs) linking the anion and neutral CH OO species vibra-tional states. FCFs were calculated using the ezSpectrum 3.0 program which is madefreely available by Mozhayskiy and Krylov. The program produces FCFs in either theparallel mode approximation as products of one-dimensional harmonic wavefunctions, orby undertaking Duschinsky rotations of the normal modes between states. Input to thecode consists of the output from the ab initio calculations, being geometries, vibrational4requencies, and vibrational normal mode vectors. The predicted stick spectra were con-voluted with a Gaussian response function of width . eV to simulate an experimentalspectrum. The geometry of the neutral Criegee intermediate is well known from previous high levelcalculations (see Reference [12] and References cited therein). It has been shown thatthe C − O and O − O bond lengths are sensitive to the level of theory used is, and itis noted that the values predicted from CCSD(T)/A (cid:48)
VQZ calculations are in line withthose reported in references [11] and [12]. Our full data set is provided in Table 1, anda visual comparison of the two species is provided in Figure 1. We predict values of . Å and . Å for the C − O and O − O bond lengths respectively, which is in verygood agreement with the CCSD(T)/AVTZ calculations of Nguyen et al. ( . Å and . Å from reference [12]).
Figure 1:
The CH OO anion and neutral species. Bond lengths are from CCSD(T)/A (cid:48)
VQZcalculations. Full geometric data are presented in Table 1.
The agreement is also very good between our results and those from Fang et al. CAS-(8,6)+1+2/cc-pVDZ calculations which result in C − O and O − O bond lengths of . Å and . Å respectively. Our CCSD(T)/A (cid:48)
VQZ harmonic vibration frequenciesare also in good agreement with those reported previously as shown in Table 1.To the best of our knowledge, the geometry of the analogous Criegee anion CH OO – and the geometrical parameters (bond lengths r , bond angles θ , and torsional angles φ ) at the CCSD(T)/A (cid:48) VQZ level of theory are presented here for the first time. Inessence, the structure of the anion is similar to the neutral, as can be seen in Figure 1,however features longer C − O and O − O bond lengths. The C − O bond length increasesby . Å, while the O-O bond length increases by . Å. In addition to these twostructural differences, the anion species is no longer of C s symmetry as the hydrogenatoms have moved out of the plane defined by the C − O − O atoms. As presented inTable 1, the H − C − O − O dihedral angles are − . ◦ and − . ◦ for the Criegee anion,whereas in the neutral species the values are ◦ and ◦ .5 able 1: Computed geometric parameters of the CH OO anion and neutral species at theCCSD(T) level of theory, with A (cid:48)
VQZ or A (cid:48)
VTZ basis sets.
Anion Anion TS Neutral
Basis Set CCSD(T)/A (cid:48)
VQZ CCSD(T)/A (cid:48)
VTZ CCSD(T)/A (cid:48)
VQZ r (C − H) [Å] 1.086, 1.090 † † † r (C − O) [Å] .
334 1 .
317 1 . r (O − O) [Å] .
450 1 .
589 1 . θ (H − C − H) [ ◦ ] . . . θ (H − C − O) [ ◦ ] 116.4, 113.0 † † † θ (C − O − O) [ ◦ ] . . . φ (H − C − H − O) [ ◦ ] -145.2, 144.1 † -155.9, -156.1 † − . φ (H − C − O − O) [ ◦ ] -17.9, -164.8 † † † † Where two values are present, the first corresponds to the hydrogen closestto the terminal oxygen.
In order to rationalise the differences in anion and neutral geometries we have per-formed natural bond orbital (NBO) calculations to determine the population of thebonding, anti-bonding, and lone pair natural orbitals. These data, in terms of orbitaloccupancies, are provided in the supplementary information (Table S4). For the anionspecies increased electron density is predicted in the lone pair orbitals of the carbon, andfor the oxygen bound to carbon. The pyramidal nature of the anion complex, comparedwith the planar neutral, can be rationalised as the population in the carbon lone pairorbital. The NBO calculations also reveal decreased electron density in C − O and O − Obonding orbitals for the anion, leading to the increase in the bond lengths. There is alsoa marked decrease in the population of the C − O anti-bonding orbital, whereas the O − Oanti-bonding orbital occupancy barely changes. This explains the larger change in theO − O bond length compared with the C − O bond length.The vibrational modes of the neutral species have been ordered according to the usualnumbering scheme appropriate for a C s symmetry molecule (wavenumber descending in a (cid:48) , and then descending in a (cid:48)(cid:48) symmetry). For ease of comparison between the anion andneutral modes, we have adopted the same order for the anion species even though theyare all of a symmetry. In any event, the mode description for each mode is provided in thetable. We note that the increased O − O bond length in the anion species is reflected in areduction of the frequency of the O − O stretching mode, ν , from cm − to cm − ,similarly the C − O bond length increase leads to a reduction in vibrational frequency ofmodes ν and ν . The CH wagging mode has also decreased in frequency in the anionspecies. The components of the W3-F12 total atomisation energies for the CH OO and CH OO – species are given in Table 3. At the W2-F12 level, the relativistic, all-electron CCSD(T)contributions to TAE add up to . kJ mol − for CH OO, and . kJ mol − forCH OO – . The TAE for the Criegee intermediate is higher than the W1 value ofNguyen et al. by . kJ mol − . The lion’s share of the difference comes from the va-6 able 2:
Computed vibrational data of the CH OO anion and neutral species at theCCSD(T)/A (cid:48)
VQZ level, and comparison with recent published work.
Anion Neutral Mode descriptionMethod CCSD(T) CCSD(T) CCSD(T) NEVPT2Basis Set A (cid:48)
VQZ A (cid:48)
VQZ AVTZ AVDZApprox. Har. Har. Har. Anh. Har. ν [cm − ] 3185 a a (cid:48) a (cid:48) a (cid:48) a (cid:48) Asymmetric CH stretch ν [cm − ] 3048 a a (cid:48) a (cid:48) a (cid:48) a (cid:48) Symmetric CH stretch ν [cm − ] 1422 a a (cid:48) a (cid:48) a (cid:48) a (cid:48) CH scissor/CO stretch ν [cm − ] 1252 a a (cid:48) a (cid:48) a (cid:48) a (cid:48) CO stretch/CH scissor ν [cm − ] 1164 a a (cid:48) a (cid:48) a (cid:48) a (cid:48) CH rocking ν [cm − ] 776 a a (cid:48) a (cid:48) a (cid:48) a (cid:48) OO stretch ν [cm − ] 466 a a (cid:48) a (cid:48) a (cid:48) a (cid:48) COO deformation † ν [cm − ] 601 a a (cid:48)(cid:48) a (cid:48)(cid:48) a (cid:48)(cid:48) a (cid:48)(cid:48) CH wagging † ν [cm − ] 316 a a (cid:48)(cid:48) a (cid:48)(cid:48) a (cid:48)(cid:48) a (cid:48)(cid:48) CH twistingReference This work This work [12] [9] as in [9] † The ordering of the modes of the anion has been changed to reflect that ofthe neutral, for direct comparison. lence CCSD(T) components which are closer to the basis set limit in W2-F12 theory(Table S2 of the Supporting Information). The reminder of the difference comes mostlyfrom our better geometry and ZPVE and from the DBOC contribution, which is notincluded in the W1 values.We now turn our attention to the post-CCSD(T) contributions to the TAE. Table S3Table S3 of the Supporting Information provides a number of a priori diagnostics forthe importance of nondynamical correlation effects, namely the percentage of the totalatomisation energy accounted for by the SCF and (T) triples contributions from W3-F12 theory (as well as the coupled cluster T and D diagnostics). The CH OOneutral and anion species considered in the present study exhibit mild-to-moderate non-dynamical correlation effects; % to % of the atomisation energy is accounted forat the SCF level, and . % to . % by the (T) triples. The T diagnostics of above . (namely, . to . ) and D diagnostics of above . ( . to . ) also in-dicate that post-CCSD(T) excitations may have nontrivial contributions. The generallygood performance of the CCSD(T)/CBS level of theory in computational thermochem-istry can typically be attributed to the large degree of cancellation between higher-ordertriples contributions, T -(T), and post-CCSDT contributions. For systems dominatedby dynamical correlation, these contributions are of similar magnitudes, however, theT -(T) excitations tend to universally decrease the atomisation energies whereas thepost-CCSDT excitations tend to universally increase the atomisation energies. In thisregard, we find that for the CH OO – anion there is a significant degree of cancellation be-tween the T -(T) contribution ( − . kJ mol − ) and the (Q) contribution ( . kJ mol − ).Resulting in a post-CCSD(T) contribution of . kJ mol − . However, for the Criegee in-termediate there is significantly poorer cancellation between the T -(T) ( − . kJ mol − )and (Q) contributions ( . kJ mol − ). Therefore, the post-CCSD(T) contributions in-crease the atomisation energy of CH OO by as much as . kJ mol − . We note that theinclusion of higher-order quadruple contributions, T -(Q), is likely to reduce the magni-tude of the connected quadruple excitations, and therefore our CCSDT(Q)/CBS values7hould be regarded as upper limits of the TAEs. Table 3:
Component breakdown of the W3-F12 total atomisation energies and heats of for-mation of the CH OO neutral and anion species, electron affinity of CH OO, andbarrier height for the CH OO – CH O + O – reaction (in kJ mol − ). CH OO CH OO – E † EA E ∗ BH SCF . . . . CCSD . . . − . (T) . . − . − . T –(T) − . − . . − . (Q) . . − . − . Inner-Shell . . − . . Scalar Relativistic − . − . − . − . Spin-Orbit − . − . . . DBOC . . − . . TAE e . . . . ZPVE . . − . . TAE . . . . H f , . . . . H f , . . . . † Energy for the CH OO – CH OO + e – reaction. ∗ Barrier height for the CH OO – CH O + O – reaction. Overall, our best relativistic, all-electron CCSDT(Q)/CBS atomisation energies (Ta-ble 3) are . kJ mol − (CH OO) and . kJ mol − (CH OO – ). These correspondto heats of formation at K of . kJ mol − (CH OO) and . kJ mol − (CH OO – ),and heats of formation at K of . kJ mol − (CH OO) and . kJ mol − (CH OO – ).In accordance with the large post-CCSD(T) contributions for the Criegee intermediateour W3-F12 heats of formation are lower than the W1 values of Nguyen et al. ( ∆ H f , =113 . kJ mol − and ∆ H f , = 105 . kJ mol − ).Using the W3-F12 heats of formation for the CH OO neutral and anion species electronaffinities for the Criegee intermediate of . kJ mol − at K and . kJ mol − at Kwere obtained. It is noted that the post-CCSD(T) contributions to the electron affinityadd up to as much as . kJ mol − . OO – with respect to dissociation In order to determine the stability of the Criegee anion species we modelled the reactionprofile for dissociation to the products formaldehyde and oxide. This was achieved byoptimising the geometry of the transition state (TS) linking the reactant CH OO – andthe products CH O and O – species. The W3-F12 procedure was applied to the TS, anion,and products with the results shown in Figure 2. It is clear that an appreciable barrier todissociation exists of . kJ mol − , and therefore should a synthetic route to the anionbe found it is likely that it should survive long enough for interrogation.8 igure 2: Reaction profile illustrating the dissociation channel of the Criegee anionCH OO – to the products CH O + O – calculated at the W3-F12 level. OO – Armed with the CCSD(T)/A (cid:48)
VQZ geometries, vibrational frequencies, and normal modevectors, we are in a position to predict the form of the anion photoelectron spectrum.Therefore the ezSpectrum 3.0 code was employed to simulate the vibronic transitions ata temperature of K, which is appropriate for species entrained in a molecular beamproduced via supersonic expansion. Up to quanta were allowed in each excited statevibrational mode (i.e. the modes of the neutral CH OO species). In Figure 3, a stickspectrum is presented which is the result of applying the ezSpectrum code with theDuschinsky approach. We also performed simulations using the parallel mode approx-imation, however, the differences between the forms of the two predicted spectra wereinsignificant and do not warrant further discussion. The grey part of the spectrum marksthe combination bands, whereas the red part represents the pure progressions; togetherthey form the fully predicted spectrum. Data pertaining to this spectrum, including pre-dicted line positions, intensities, Franck-Condon Factors, and assignments, are providedin the supplementary information (Table S5 and Table S6) accompanying this Letter.The majority of the pure progressions (marked red in Figure 3) are for the modes ν and ν which correspond to the O − O stretching and CH wagging modes respectively. Thefact that these two modes display the longest progressions is consistent with the geometrychanges observed between the anion and neutral species. Referring to the data in Table 1,the O − O bond length is predicted to decrease by . Å, while the two hydrogen atomsmove into the C − O − O plane, with the pair of H − C − O − O dihedral angles changing from − . ◦ and − . ◦ to . ◦ and . ◦ . The low panel of Figure 3 includes the possiblecombination bands, i.e. those with intensity above the cut off threshold of . au. Themajor combination bands are again those associate with the O − O and CH waggingmodes.Again, a full list of line positions including assignments is provided in the supplemen-9 igure 3: Predicted anion photoelectron stick spectra (red marks the pure progressions). . . . . . . E BE [eV]0 . . . . . . I n t e n s i t y [ a . u .] tary material. To provide a clearer picture of what an experimental spectrum might looklike, we convoluted the line spectrum with a Gaussian response function whose full widthat half maximum was set to . eV and the resulting simulated spectrum is shown inFigure 4. We believe that this is appropriate as this resolution is achievable by thestate-of-the-art anion photoelectron spectrometers in use today.As a final note, when considering the mass selected photoelectron spectrum of theCH OO – anion one cannot discount the possibility that a van der Waals complex of theform O – · · · CH O may also be synthesised in addition to the covalently bound CH OO – anion. This possibility needs to be taken into account, however, fortuitously the ioni-sation energy of the O – anion is a great deal larger than for CH OO – , with the mostrecent determination of the electron affinity of the O neutral being .
439 157 eV. TheO – · · · CH O species should be essentially a perturbed O – anion, due to the weak interac-tion in a van Der Waals species, and in addition the electron binding energy of the aniongenerally increases upon formation of a van der Waals complex. Therefore, the Criegeeanion can be preferentially targeted by selecting a photodetachment photon energy below . eV. 10 igure 4: Simulated photoelectron spectrum of CH OO – with the stick spectrum shown inFigure 3 convoluted with Gaussian response function (fwhm = meV ). . . . . . . E BE [eV]0 . . . . . . I n t e n s i t y [ a . u .] In summary, we have shown that the CH OO – anion with an analogous structure to theneutral Criegee intermediate exists. The anion is stable with respect to dissociation ofthe O − O bond, with a barrier of . kJ mol − , and the electron is bound by . eV.The major geometric differences between the anion and neutral are in the increased O − Obond length, and the movement of the terminal hydrogen atoms into the plane formedby the C − O − O atoms. Progressions involving both of these modes are prominent in thepredicted photoelectron spectrum.
Acknowledgements
We gratefully acknowledge funding (to A.K.) from the Australian Research Council (Dis-covery Project Grant: DP
110 102 336 ) and the generous allocation of computing timefrom the National Computational Infrastructure (NCI) National Facility.
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CCSD(T) Optimised Geometries (Cartesian Coordinates in Å ). CH OO optimised at CCSD(T)/A (cid:48)
VQZ x y z C .
074 790 954 2 − .
206 575 928 2 0 .
000 000 000 0 H .
979 677 245 9 0 .
382 186 173 1 0 .
000 000 000 0 O − .
001 515 793 3 0 .
468 205 695 8 0 .
000 000 000 0 O − .
165 017 699 7 − .
202 933 042 7 0 .
000 000 000 0 H .
010 308 292 8 − .
287 087 898 1 0 .
000 000 000 0 CH OO – optimised at CCSD(T)/A (cid:48) VQZC .
101 533 191 7 − .
229 149 572 5 − .
063 060 084 4 H .
016 025 265 1 0 .
292 700 141 6 0 .
217 757 295 6 O .
015 166 596 1 0 .
540 425 223 7 0 .
018 566 420 1 O − .
202 320 126 9 − .
247 146 831 5 − .
011 696 225 5 H .
965 446 073 7 − .
282 404 961 2 0 .
162 484 594 0 CH OO optimised at CCSD(T)/A (cid:48)
VTZC .
076 818 676 4 − .
207 035 849 0 0 .
000 000 000 0 H .
982 960 111 8 0 .
381 979 796 1 0 .
000 000 000 0 O − .
002 618 673 2 0 .
471 610 046 4 0 .
000 000 000 0 O − .
171 291 535 4 − .
204 129 142 2 0 .
000 000 000 0 H .
012 374 420 3 − .
288 629 851 3 0 .
000 000 000 0 CH OO – optimised at CCSD(T)/A (cid:48) VTZC .
103 699 235 3 − .
229 595 995 0 − .
067 263 693 4 H .
018 367 937 7 0 .
291 711 456 4 0 .
219 638 441 0 O .
014 965 709 8 0 .
544 038 620 6 0 .
019 280 622 0 O − .
208 803 653 1 − .
248 724 066 3 − .
011 729 182 8 H .
967 621 770 2 − .
283 006 015 7 0 .
164 125 813 2 [CH O · · · O] – optimised at CCSD(T)/A (cid:48) VTZC .
074 380 845 2 − .
232 703 156 6 − .
027 400 208 0 H .
060 086 786 0 − .
085 529 818 0 − .
710 223 499 9 O .
101 821 301 9 0 .
650 944 598 5 − .
116 593 427 5 O − .
165 421 797 0 − .
282 942 983 5 0 .
101 191 128 7 H .
618 109 863 8 − .
335 489 640 4 0 .
919 673 006 7 able S2: Comparison between W2-F12 (this work) and W1 a CCSD(T)/CBS total atomi-sation energies for the Criegee intermediate (in kJ mol − ). CCSD(T)/CBS CV+SR SO ZPVE TAE(0)W2-F12 . . − . . . W1 . . − . . . a Taken from M.T. Nguyen, T.L. Nguyen, V.T. Ngan, H.M.T. Nguyen, Chem.Phys. Lett., 448 (2007) 183.
Table S3:
Diagnostics for importance of nondynamical correlation. CH OO CH OO – [CH O · · · O] – TAE[SCF] a [%] . . . TAE e [(T)] b [%] . . . T1 c .
044 0 .
034 0 . D1 c .
176 0 .
122 0 . a Percentages of the total atomisation energy accounted by the SCF componentrelative to nonrelativistic, clamped-nuclei, valence CCSDT(Q) values from W3-F12 theory. b Percentages of the total atomisation energy accounted by the (T) component rel-ative to nonrelativistic, clamped-nuclei, valence CCSDT(Q) values from W3-F12theory. c From a CCSD(T)/A (cid:48)
VTZ calculation.
Table S4:
Orbital occupancies from NBO 6.0 calculations for anion and neutral CH OO. CH OO CH OO – C − O bonding . . O − O bonding . . C − O anti-bonding . . O − O anti-bonding . . C lone pair . . O lone pair . . O lone pair (terminal) . . C − H bonding . /1.9955 . /1.9956C − H anti-bonding . /0.0153 . /0.0166 Table S5: ezSpectrum 3.0 simulations from CCSD(T)/A (cid:48)
VQZ geometries, harmonic fre-quencies and normal mode vectors. Data pertain to application of the Duschinskyformalism. Simulation temperature of K , intensity threshold of . × − au ,maximum number of quanta in excited state v = . E BH [eV] Intensity [au] FCF [au] Transition . .
494 071 × − .
579 263 × − → . .
634 408 × − .
506 269 × − → . .
523 071 × − .
902 654 × − → . .
739 918 × − .
655 270 × − → . .
875 963 × − − .
695 866 × − → Continued on next page able S5: Table S5 – Continued from previous page E BH [eV] Intensity [au] FCF [au] Transition . .
029 376 × − .
208 390 × − → . .
595 634 × − .
094 736 × − → . .
042 241 × − .
228 376 × − → . .
063 235 × − − .
031 133 × − → . .
450 907 × − .
383 026 × − → . .
244 429 × − − .
902 170 × − → . .
734 344 × − .
229 096 × − → . .
948 150 × − .
154 069 × − → . .
995 556 × − − .
467 164 × − → . .
913 721 × − .
383 373 × − → . .
349 666 × − .
889 579 × − → . .
983 042 × − − .
727 148 × − → . .
198 228 × − − .
688 526 × − → . .
948 531 × − .
395 898 × − → . .
224 151 × − .
037 129 × − → . .
766 484 × − − .
401 350 × − → . .
114 799 × − − .
338 860 × − → . .
241 314 × − .
289 392 × − → . .
204 468 × − .
660 802 × − → . .
163 621 × − − .
482 664 × − → . .
342 162 × − .
056 495 × − → . .
426 701 × − − .
853 803 × − → . .
106 530 × − − .
051 917 × − → . .
269 727 × − − .
563 322 × − → . .
292 793 × − .
137 011 × − → . .
430 479 × − .
857 029 × − → . .
659 486 × − − .
522 956 × − → . .
798 860 × − .
163 489 × − → . .
088 714 × − .
394 305 × − → . .
480 573 × − − .
899 638 × − → . .
261 825 × − − .
552 217 × − → . .
497 083 × − .
869 216 × − → . .
066 484 × − − .
265 707 × − → . .
054 001 × − .
026 646 × − → . .
558 704 × − .
058 364 × − → . .
149 745 × − .
024 855 × − → . .
990 639 × − − .
410 900 × − → . .
045 778 × − − .
233 848 × − → . .
989 827 × − − .
460 747 × − → . .
922 762 × − .
386 637 × − → . .
573 238 × − .
072 710 × − → . .
247 227 × − − .
531 610 × − → . .
487 538 × − .
342 549 × − → . .
991 816 × − − .
995 907 × − → . .
329 596 × − − .
054 439 × − → . .
572 315 × − .
563 653 × − → . .
023 621 × − .
832 600 × − → . .
160 158 × − .
675 847 × − → . .
457 742 × − − .
541 209 × − → . .
438 783 × − .
938 404 × − → . .
752 186 × − .
398 371 × − → Continued on next page able S5: Table S5 – Continued from previous page E BH [eV] Intensity [au] FCF [au] Transition . .
991 340 × − − .
317 705 × − → . .
404 273 × − − .
604 809 × − → . .
061 017 × − − .
257 325 × − → . .
585 400 × − .
084 683 × − → . .
272 149 × − .
127 896 × − → . .
717 748 × − .
144 572 × − → . .
030 295 × − .
005 045 × − → . .
150 493 × − − .
565 821 × − → . .
384 912 × − − .
818 000 × − → . .
127 578 × − .
592 475 × − → . .
501 801 × − .
917 602 × − → . .
556 307 × − − .
750 042 × − → . .
200 151 × − − .
280 384 × − → . .
032 836 × − − .
508 698 × − → . .
554 232 × − .
053 941 × − → . .
159 001 × − .
026 384 × − → . .
252 689 × − − .
539 335 × − → . .
371 008 × − − .
893 269 × − → . .
484 399 × − .
852 790 × − → . .
984 658 × − .
060 211 × − → . .
535 624 × − .
035 498 × − → . .
308 203 × − .
511 614 × − → . .
422 650 × − .
328 658 × − → . .
052 832 × − − .
026 076 × − → . .
256 416 × − − .
706 501 × − → . .
074 757 × − − .
278 348 × − → . .
188 439 × − − .
447 374 × − → . .
234 426 × − .
111 047 × − → . .
548 573 × − .
747 467 × − → . .
184 878 × − .
674 268 × − → . .
641 748 × − − .
051 849 × − → . .
421 348 × − − .
706 363 × − → . .
762 033 × − − .
197 658 × − → . .
661 851 × − .
076 580 × − → . .
269 648 × − − .
295 571 × − → . .
274 924 × − .
538 290 × − → . .
648 697 × − .
376 699 × − → . .
568 890 × − − .
751 162 × − → . .
327 986 × − − .
515 549 × − → . .
443 090 × − .
798 803 × − → . .
897 957 × − − .
383 267 × − → . .
925 760 × − − .
265 589 × − → . .
457 639 × − − .
817 903 × − → . .
189 798 × − − .
487 930 × − → . .
861 335 × − .
349 144 × − → . .
147 827 × − .
026 531 × − → . .
205 411 × − .
471 903 × − → . .
429 983 × − .
725 800 × − → . .
100 090 × − .
664 599 × − → . .
452 298 × − − .
810 903 × − → . .
572 458 × − − .
258 757 × − → Continued on next page able S5: Table S5 – Continued from previous page E BH [eV] Intensity [au] FCF [au] Transition . .
619 512 × − − .
024 317 × − → . .
979 348 × − − .
445 271 × − → . .
967 069 × − .
435 165 × − → . .
874 711 × − .
981 913 × − → . .
006 310 × − .
479 185 × − → . .
572 140 × − − .
976 738 × − → . .
653 251 × − − .
066 019 × − → . .
174 987 × − .
634 702 × − → . .
150 417 × − − .
024 966 × − → . .
452 092 × − .
907 248 × − → . .
402 676 × − − .
745 231 × − → . .
646 926 × − .
058 233 × − → . .
113 242 × − .
597 001 × − → . .
633 327 × − .
041 445 × − → . .
171 091 × − − .
422 121 × − → . .
798 387 × − − .
927 039 × − → . .
053 950 × − − .
526 255 × − → . .
039 515 × − − .
653 208 × − → . .
677 181 × − − .
382 684 × − → . .
310 346 × − .
943 768 × − → . .
394 883 × − .
893 754 × − → . .
332 451 × − .
707 850 × − → . .
242 485 × − .
524 890 × − → . .
561 488 × − − .
358 281 × − → . .
292 486 × − − .
595 116 × − → . .
842 437 × − − .
643 583 × − → . .
414 344 × − − .
760 776 × − → . .
064 801 × − .
544 008 × − → . .
863 561 × − .
215 755 × − → . .
107 960 × − .
017 940 × − → . .
267 901 × − − .
560 760 × − → . .
367 175 × − − .
316 716 × − → . .
604 950 × − − .
006 182 × − → . .
262 036 × − .
694 817 × − → . .
086 544 × − .
255 337 × − → . .
644 763 × − − .
055 568 × − → . .
793 326 × − − .
234 768 × − → . .
469 467 × − − .
833 363 × − → . .
994 930 × − .
466 464 × − → . .
155 773 × − .
446 528 × − → . .
020 699 × − .
453 711 × − → . .
123 509 × − .
608 154 × − → . .
708 268 × − .
133 120 × − → . .
534 052 × − − .
916 698 × − → . .
288 105 × − − .
271 935 × − → . .
547 056 × − − .
933 263 × − → . .
718 852 × − − .
592 075 × − → . .
040 294 × − .
225 359 × − → . .
728 731 × − .
593 980 × − → . .
365 628 × − .
607 290 × − → . .
240 582 × − .
039 832 × − → Continued on next page able S5: Table S5 – Continued from previous page E BH [eV] Intensity [au] FCF [au] Transition . .
151 855 × − − .
638 809 × − → . .
158 090 × − − .
645 525 × − → . .
114 148 × − − .
018 965 × − → . .
387 240 × − .
885 939 × − → . .
219 449 × − − .
284 611 × − → . .
549 313 × − .
559 163 × − → . .
663 499 × − − .
078 602 × − → . .
149 491 × − .
390 415 × − → . .
241 443 × − .
870 791 × − → . .
374 324 × − .
893 843 × − → . .
398 558 × − .
529 537 × − → . .
375 547 × − .
524 985 × − → . .
235 274 × − − .
514 646 × − → . .
965 349 × − − .
433 226 × − → . .
885 351 × − − .
342 063 × − → . .
841 581 × − .
615 642 × − → . .
788 909 × − .
281 012 × − → . .
139 057 × − .
624 994 × − → . .
681 265 × − .
383 540 × − → . .
974 229 × − .
444 224 × − → . .
813 396 × − − .
795 245 × − → . .
897 225 × − − .
382 588 × − → . .
319 568 × − − .
632 586 × − → . .
712 887 × − − .
777 208 × − → . .
321 856 × − − .
306 915 × − → . .
550 973 × − .
938 240 × − → . .
320 834 × − .
817 503 × − → . .
942 741 × − .
634 908 × − → . .
497 392 × − − .
869 615 × − → . .
393 528 × − − .
732 999 × − → . .
206 741 × − .
684 537 × − → . .
450 301 × − .
334 588 × − → . .
968 214 × − − .
822 802 × − → . .
361 233 × − − .
713 159 × − → . .
953 026 × − − .
154 842 × − → . .
092 626 × − .
305 490 × − → . .
832 699 × − .
281 003 × − → . .
398 013 × − .
323 362 × − → . .
043 919 × − .
520 972 × − → . .
606 832 × − .
008 531 × − → . .
031 252 × − − .
211 312 × − → . .
609 689 × − − .
108 512 × − → . .
484 412 × − − .
984 388 × − → . .
175 673 × − − .
428 808 × − → . .
805 475 × − .
608 731 × − → . .
603 466 × − .
102 417 × − → . .
135 841 × − .
370 224 × − → . .
094 247 × − − .
307 940 × − → . .
224 871 × − − .
285 798 × − → . .
852 977 × − − .
304 622 × − → . .
386 489 × − .
723 559 × − → Continued on next page able S5: Table S5 – Continued from previous page E BH [eV] Intensity [au] FCF [au] Transition . .
358 369 × − .
891 084 × − → . .
204 721 × − − .
470 910 × − → . .
298 888 × − .
509 758 × − → . .
099 998 × − .
469 817 × − → . .
238 332 × − .
690 415 × − → . .
287 162 × − − .
878 743 × − → . .
419 347 × − − .
723 848 × − → . .
310 346 × − − .
051 286 × − → . .
939 581 × − − .
817 726 × − → . .
902 473 × − − .
811 134 × − → . .
889 895 × − .
624 861 × − → . .
110 272 × − .
332 074 × − → . .
272 892 × − .
567 761 × − → . .
186 973 × − .
487 363 × − → . .
245 923 × − − .
529 763 × − → . .
126 893 × − − .
356 923 × − → . .
578 640 × − − .
564 886 × − → . .
997 283 × − .
999 547 × − → . .
119 296 × − .
345 588 × − → . .
022 243 × − .
454 026 × − → . .
080 050 × − − .
286 411 × − → . .
126 162 × − − .
850 642 × − → . .
125 901 × − .
850 597 × − → . .
454 356 × − − .
335 456 × − → . .
125 597 × − .
263 978 × − → . .
280 548 × − .
698 249 × − → . .
434 008 × − .
786 829 × − → . .
032 269 × − .
212 894 × − → . .
470 989 × − − .
339 014 × − → . .
117 192 × − − .
342 442 × − → . .
249 823 × − − .
743 230 × − → . .
041 178 × − − .
226 728 × − → . .
247 339 × − .
531 768 × − → . .
692 415 × − .
113 898 × − → . .
121 766 × − .
474 220 × − → . .
071 148 × − − .
272 840 × − → . .
214 929 × − − .
492 976 × − → . .
821 899 × − .
611 877 × − → . .
895 717 × − .
625 970 × − → . .
772 435 × − − .
602 390 × − → . .
064 710 × − .
250 491 × − → . .
457 520 × − − .
730 846 × − → . .
040 460 × − − .
653 386 × − → . .
086 454 × − .
467 074 × − → . .
835 989 × − .
136 238 × − → . .
679 067 × − .
383 079 × − → . .
486 771 × − − .
546 914 × − → . .
037 241 × − − .
244 380 × − → . .
047 977 × − − .
459 263 × − → . .
204 542 × − − .
281 347 × − → . .
650 680 × − .
377 116 × − → Continued on next page able S5: Table S5 – Continued from previous page E BH [eV] Intensity [au] FCF [au] Transition . .
235 563 × − .
869 767 × − → . .
398 049 × − .
323 370 × − → . .
502 701 × − − .
876 469 × − → . .
396 327 × − − .
529 096 × − → . .
199 924 × − .
280 334 × − → . .
457 512 × − .
817 737 × − → . .
131 045 × − .
265 181 × − → . .
681 297 × − − .
946 404 × − → . .
087 894 × − − .
255 636 × − → . .
698 106 × − .
949 255 × − → . .
024 421 × − − .
650 362 × − → . .
057 134 × − − .
248 807 × − → . .
269 810 × − − .
875 728 × − → . .
346 853 × − .
057 262 × − → . .
154 857 × − − .
674 856 × − → . .
656 530 × − .
378 346 × − → . .
908 233 × − − .
430 686 × − → Table S6: ezSpectrum 3.0 simulations from CCSD(T)/A (cid:48)
VQZ geometries, harmonic fre-quencies and normal mode vectors. Data pertain to application of the Par-allel Mode formalism. Simulation temperature of K , intensity threshold of . × − au , maximum number of quanta in excited state v = . E BH [eV] Intensity [au] FCF [au] Transition . .
631 643 × − .
622 234 × − → . .
001 912 × − .
072 420 × − → . .
771 837 × − .
787 802 × − → . .
577 728 × − .
605 530 × − → . .
997 164 × − − .
731 232 × − → . .
608 812 × − .
934 078 × − → . .
381 422 × − .
814 999 × − → . .
863 135 × − .
316 405 × − → . .
095 256 × − − .
046 545 × − → . .
899 438 × − .
999 598 × − → . .
696 651 × − − .
547 616 × − → . .
662 671 × − .
828 376 × − → . .
612 615 × − .
759 097 × − → . .
851 304 × − − .
975 114 × − → . .
787 438 × − .
336 951 × − → . .
427 003 × − .
535 153 × − → . .
935 760 × − − .
713 406 × − → . .
081 732 × − − .
562 600 × − → . .
013 154 × − .
418 857 × − → . .
432 443 × − .
903 867 × − → Continued on next page able S6: Table S6 – Continued from previous page E BH [eV] Intensity [au] FCF [au] Transition . .
804 530 × − − .
131 219 × − → . .
862 250 × − .
976 953 × − → . .
312 146 × − .
755 125 × − → . .
824 965 × − .
271 960 × − → . .
851 083 × − − .
205 709 × − → . .
072 817 × − − .
035 769 × − → . .
121 914 × − − .
606 424 × − → . .
247 381 × − .
116 862 × − → . .
397 348 × − .
828 678 × − → . .
579 943 × − − .
469 902 × − → . .
567 147 × − .
758 067 × − → . .
278 709 × − .
297 544 × − → . .
826 363 × − .
185 761 × − → . .
310 291 × − − .
287 175 × − → . .
669 966 × − − .
944 481 × − → . .
945 301 × − .
438 299 × − → . .
407 304 × − − .
751 406 × − → . .
754 129 × − − .
784 624 × − → . .
015 601 × − .
007 770 × − → . .
558 786 × − .
058 445 × − → . .
295 332 × − .
509 050 × − → . .
035 703 × − − .
426 781 × − → . .
319 679 × − − .
705 491 × − → . .
039 083 × − − .
515 621 × − → . .
991 109 × − .
447 674 × − → . .
971 910 × − .
404 247 × − → . .
370 873 × − .
869 161 × − → . .
940 544 × − − .
405 161 × − → . .
847 190 × − .
418 096 × − → . .
025 713 × − − .
012 775 × − → . .
603 663 × − − .
098 978 × − → . .
680 688 × − .
946 301 × − → . .
585 570 × − .
566 237 × − → . .
009 317 × − − .
176 975 × − → . .
260 983 × − .
293 683 × − → . .
296 695 × − .
792 385 × − → . .
265 460 × − .
557 330 × − → . .
772 185 × − − .
141 812 × − → . .
439 087 × − − .
625 014 × − → . .
078 442 × − − .
558 994 × − → . .
586 720 × − .
085 981 × − → . .
221 826 × − .
105 362 × − → . .
390 178 × − .
888 945 × − → . .
930 333 × − .
393 555 × − → . .
425 261 × − .
775 263 × − → . .
378 490 × − − .
153 409 × − → . .
869 222 × − − .
220 307 × − → . .
166 933 × − .
627 551 × − → . .
747 972 × − .
122 068 × − → . .
201 499 × − − .
212 142 × − → . .
011 893 × − − .
451 916 × − → Continued on next page able S6: Table S6 – Continued from previous page E BH [eV] Intensity [au] FCF [au] Transition . .
949 553 × − − .
415 374 × − → . .
566 851 × − .
972 312 × − → . .
823 499 × − .
413 193 × − → . .
378 473 × − − .
712 779 × − → . .
595 269 × − − .
755 952 × − → . .
602 771 × − .
003 463 × − → . .
098 724 × − .
140 535 × − → . .
506 364 × − .
006 360 × − → . .
831 135 × − .
971 723 × − → . .
156 662 × − − .
075 482 × − → . .
914 188 × − − .
398 322 × − → . .
169 720 × − − .
677 633 × − → . .
413 933 × − − .
760 230 × − → . .
868 369 × − .
422 472 × − → . .
367 354 × − .
169 339 × − → . .
322 301 × − .
819 026 × − → . .
823 242 × − − .
612 134 × − → . .
900 788 × − − .
359 803 × − → . .
004 699 × − − .
002 347 × − → . .
592 484 × − − .
990 593 × − → . .
210 075 × − .
701 144 × − → . .
659 333 × − − .
580 568 × − → . .
019 328 × − .
453 432 × − → . .
367 313 × − .
608 565 × − → . .
450 651 × − .
539 813 × − → . .
886 389 × − − .
144 263 × − → . .
153 200 × − .
270 066 × − → . .
304 955 × − .
612 415 × − → . .
779 445 × − .
603 737 × − → . .
991 705 × − − .
447 796 × − → . .
190 189 × − .
681 453 × − → . .
615 694 × − − .
114 385 × − → . .
226 800 × − − .
501 384 × − → . .
441 225 × − − .
796 347 × − → . .
533 726 × − .
033 613 × − → . .
472 336 × − .
204 529 × − → . .
341 210 × − .
838 606 × − → . .
691 047 × − .
113 045 × − → . .
396 062 × − .
736 391 × − → . .
317 948 × − − .
630 355 × − → . .
206 839 × − − .
059 161 × − → . .
722 161 × − − .
217 433 × − → . .
198 445 × − − .
688 758 × − → . .
538 940 × − − .
353 495 × − → . .
799 413 × − .
241 949 × − → . .
261 782 × − − .
694 769 × − → . .
268 886 × − .
533 671 × − → . .
598 904 × − .
097 944 × − → . .
606 802 × − − .
005 666 × − → . .
909 612 × − − .
369 911 × − → . .
493 776 × − .
910 818 × − → Continued on next page able S6: Table S6 – Continued from previous page E BH [eV] Intensity [au] FCF [au] Transition . .
558 551 × − − .
091 691 × − → . .
300 868 × − .
881 123 × − → . .
817 330 × − − .
263 015 × − → . .
266 681 × − − .
294 925 × − → . .
569 935 × − .
962 241 × − → . .
339 679 × − .
837 023 × − → . .
737 953 × − .
168 876 × − → . .
650 211 × − .
941 124 × − → . .
076 560 × − − .
281 097 × − → . .
806 910 × − − .
620 308 × − → . .
854 484 × − − .
342 738 × − → . .
947 616 × − − .
153 984 × − → . .
033 797 × − − .
834 395 × − → . .
931 754 × − − .
435 519 × − → . .
769 142 × − .
814 274 × − → . .
957 420 × − .
424 274 × − → . .
610 321 × − .
012 880 × − → . .
683 453 × − − .
585 238 × − → . .
318 037 × − − .
630 478 × − → . .
966 744 × − − .
346 702 × − → . .
559 858 × − − .
949 504 × − → . .
173 959 × − − .
274 634 × − → . .
164 797 × − .
652 738 × − → . .
277 839 × − .
540 519 × − → . .
113 790 × − .
848 472 × − → . .
484 478 × − − .
852 892 × − → . .
855 380 × − − .
618 278 × − → . .
633 730 × − − .
041 943 × − → . .
551 398 × − .
559 570 × − → . .
640 553 × − .
576 927 × − → . .
868 952 × − − .
422 592 × − → . .
486 206 × − − .
855 134 × − → . .
122 024 × − − .
606 543 × − → . .
188 868 × − − .
861 620 × − → . .
756 926 × − .
191 570 × − → . .
813 880 × − .
938 213 × − → . .
003 111 × − .
236 763 × − → . .
623 433 × − .
029 184 × − → . .
680 514 × − .
111 352 × − → . .
290 947 × − − .
592 975 × − → . .
690 753 × − − .
543 708 × − → . .
666 392 × − − .
163 712 × − → . .
103 708 × − − .
322 210 × − → . .
425 463 × − − .
329 262 × − → . .
033 779 × − .
005 625 × − → . .
113 009 × − − .
667 023 × − → . .
611 601 × − .
368 882 × − → . .
181 429 × − .
466 397 × − → . .
828 439 × − .
276 025 × − → . .
476 666 × − .
842 741 × − → . .
049 342 × − − .
526 966 × − → Continued on next page able S6: Table S6 – Continued from previous page E BH [eV] Intensity [au] FCF [au] Transition . .
163 277 × − − .
272 285 × − → . .
817 620 × − − .
263 355 × − → . .
324 156 × − − .
638 895 × − → . .
422 640 × − .
922 032 × − → . .
431 054 × − − .
330 462 × − → . .
130 807 × − .
851 457 × − → . .
780 098 × − − .
219 121 × − → . .
088 618 × − .
299 421 × − → . .
002 857 × − .
166 792 × − → . .
874 839 × − .
142 426 × − → . .
737 884 × − .
781 705 × − → . .
998 194 × − .
449 121 × − → . .
054 504 × − − .
247 313 × − → . .
664 648 × − − .
162 023 × − → . .
979 345 × − − .
448 983 × − → . .
743 818 × − − .
121 509 × − → . .
810 230 × − − .
410 442 × − → . .
485 131 × − .
342 036 × − → . .
900 423 × − .
245 336 × − → . .
917 319 × − .
378 720 × − → . .
132 929 × − .
365 901 × − → . .
149 648 × − .
024 839 × − → . .
488 927 × − − .
736 590 × − → . .
958 420 × − − .
291 598 × − → . .
973 163 × − − .
158 032 × − → . .
081 631 × − − .
288 815 × − → . .
067 960 × − − .
251 213 × − → . .
501 105 × − .
874 410 × − → . .
966 322 × − .
446 395 × − → . .
947 562 × − .
819 142 × − → . .
454 065 × − − .
813 221 × − → . .
600 260 × − − .
000 325 × − → . .
563 495 × − .
750 181 × − → . .
533 435 × − .
352 325 × − → . .
461 351 × − − .
731 547 × − → . .
737 446 × − − .
120 488 × − → . .
982 642 × − .
159 532 × − → . .
416 762 × − .
916 057 × − → . .
224 149 × − .
037 128 × − → . .
500 352 × − .
345 283 × − → . .
951 633 × − − .
991 928 × − → . .
233 418 × − − .
686 315 × − → . .
848 919 × − − .
299 905 × − → . .
064 645 × − − .
250 477 × − → . .
496 635 × − .
344 490 × − → . .
899 470 × − .
384 672 × − → . .
790 979 × − .
231 996 × − → . .
413 458 × − .
722 767 × − → . .
028 852 × − − .
207 573 × − → . .
057 496 × − − .
248 888 × − → . .
780 382 × − − .
219 457 × − → Continued on next page able S6: Table S6 – Continued from previous page E BH [eV] Intensity [au] FCF [au] Transition . .
315 995 × − − .
052 211 × − → . .
523 693 × − − .
742 935 × − → . .
376 515 × − .
710 142 × − → . .
799 376 × − .
607 561 × − → . .
638 031 × − .
374 454 × − → . .
234 348 × − − .
513 329 × − → . .
185 398 × − .
487 046 × − → . .
579 358 × − .
753 063 × − → . .
312 101 × − − .
704 090 × − → . .
142 149 × − − .
379 569 × − → . .
124 640 × − − .
353 565 × − → . .
756 519 × − − .
599 331 × − → . .
372 757 × − .
317 921 × − → . .
789 808 × − .
230 612 × − → . .
329 499 × − .
646 230 × − → . .
109 718 × − .
331 243 × − → . .
987 287 × − − .
457 899 × − → . .
768 842 × − − .
125 515 × − → . .
609 728 × − − .
758 574 × − → . .
145 695 × − − .
479 051 × − → . .
529 099 × − .
920 462 × − → . .
685 429 × − .
105 397 × − → . .
510 966 × − .
347 545 × − → . .
008 272 × − − .
175 330 × − → . .
109 646 × − − .
331 134 × − → . .
408 540 × − .
721 863 × − → . .
420 071 × − .
328 105 × − → . .
011 689 × − .
238 680 × − → . .
108 992 × − .
330 154 × − → . .
086 210 × − − .
255 263 × − → . .
623 306 × − − .
029 027 × − → . .
050 533 × − − .
241 193 × − → . .
647 444 × − .
058 872 × − → . .
241 894 × − .
524 051 × − → . .
234 545 × − − .
513 610 × − → . .
125 137 × − − .
020 784 × − → . .
910 661 × − .
628 814 × − → . .
660 076 × − .
580 712 × − → . .
013 419 × − − .
648 286 × − → . .
255 648 × − .
292 520 × − → . .
646 147 × − − .
376 162 × − → . .
671 659 × − .
769 776 × − → . .
554 055 × − .
748 464 × − → . .
694 963 × − .
773 980 × − → . .
119 169 × − − .
019 796 × − → . .
773 871 × − − .
602 666 × − → . .
453 827 × − − .
730 170 × − → . .
461 531 × − .
908 871 × − → . .
728 880 × − − .
393 508 × − → . .
304 873 × − − .
510 951 × − → . .
137 200 × − .
266 539 × − → Continued on next page able S6: Table S6 – Continued from previous page E BH [eV] Intensity [au] FCF [au] Transition . .
448 952 × − − .
729 277 × − → . .
274 101 × − − .
296 541 × − → . .
270 832 × − .
875 905 × − → . .
056 291 × − .
656 368 × − → . .
014 539 × − − .
648 497 × − → . .
327 516 × − − .
515 455 × − → . .
168 603 × − − .
273 456 × − →1(2v8,2v6,1v4,1v2)