M. Spoliti

MOLECULAR CONFORMATIONS AND HARMONIC FORCE FIELD OF 1,3,5-BENZENETRIOL MOLECULE FROM AB INITIO AND DENSITY FUNCTIONAL THEORY INVESTIGATIONS

Abstract The molecular conformers of the molecule 1,3,5-benzenetriol have been studied by ab initio and density functional methods to determine optimized equilibrium geometries, harmonic vibrational frequencies and relative stability. The results of the quantum-chemical calculations have been used to investigate the functional theory-infrared (FT-IR) spectrum of the 1,3,5-benzenetriol vapors trapped in Ar matrix at 12 K.

Bonding in and spectroscopic properties of gaseous triatomic molecules: Part I. Alkaline-earth metal dihalides

Abstract Molecular and atomic properties are correlated among the alkaline-earth dihalides. Unknown molecular properties are derived and molecular geometries are predicted from the use of these correlations. Empirical relations which correlate force constants, bond angles, electronegativities, ionic polarizabilities and bond distances are presented.

Infrared matrix isolation of, and bonding in, the oxides of group vib elements: O3, SO2, SeO2, and TeO2

Abstract Vibrational frequencies, force constants and geometrical parameters of the oxides of group VIB elements in rare gas matrices are compared with those in the gas phase. Bonding in these species is discussed.

The infrared spectrum of matrix isolated cuprous chloride

Abstract The infrared spectrum (500–33 cm −1 ) of cuprous chloride has been studied using the matrix isolation technique. The observed bands were assigned to the polymeric species Cu 3 Cl 3 and Cu 4 Cl 4 . The principal bond stretching force constants were calculated as 1.52 mdyn/A and 1.1 mdyn/A for the trimer and tetramer respectively, assuming for the former a planar six membered ring of alternate copper and chlorine atoms with bond angles ClCuCl 150° and CuClCu 90°, and for the latter a distorted cube with an angle ClCuCl 68°24′.

Far IR and Raman spectra of some gaseous titanium, zirconium and hafnium cyclopentadienyl chlorides

Abstract The far IR and Raman spectra of gaseous (C5H5)TiCl3 and (C5H5)2MCl2 species (M = Ti, Zr and Hf) are reported. The results are compared to the previous vibrational analysis of the corresponding species in the solid and matrix isolated phases. The assignment of the metal skeletal vibrations is reexamined in further detail on the basis of the new spectroscopic measurements. The torsional frequencies and the related potential barriers are investigated.

An ab initio HF-SCF and MP2 study of hydrogen bonding and van der Waals interactions: Low frequency vibrations of bimolecular complexes

Abstract HF-SCF and {BDMP2} calculations were carried out to investigate hydrogen bonding interactions in a series of bimolecular complexes. Calculations are reported at different levels of theory to examine the structural and vibrational effects of bimolecular interaction of molecules such as N 2 , CO, C 2 H 2 , CH 3 CN, HC 3 N, NH 2 OH, NH 3 , pyrrole, pyridine, pyrazine and benzene with HF, HCl, HCN, H 2 O and NH 3 . The van der Waals complexes He… HF, He…HCl, Ne…HF, Ne…HCl, Ar…HF, Ar…HCl, He…CO, Ne…CO, Ar…CO, HF…He, HCl… He, CO… He, HF… Ne, HCl…Ne, CO…Ne, HF… Ar, HCl… Ar and CO… Ar are also discussed.

Ab initio study on the Be2F4, Mg2F4 dimers, on the mixed dimers BeMgF4 and LiNaF2 and on the Li2BeF4, LiBCl4 and LiAlCl4 ion-pairs

Abstract This paper reports the results of Hartree-Fock self-consistent field calculations on the stable equilibrium structures (D2h and C3v,) of the halide dimers Be2F4 and Mg2F4, on those of the mixed dimer molecules BeMgF4 (C2v and C3v) and LiNaF2C2v, and on the ion-pairs Li2BeF4 (D3ddm and C2v), LiBCl4 and LiAlCl4 (C2v and C3v).

Infrared spectra of matrix-isolated gaseous ternary oxides: Part VI. The infrared spectra of lithium, cesium and thallium sulfates and indium and thallium molybdates

Abstract Infrared spectra of Li 2 SO 4 , Cs 2 SO 4 , Tl 2 SO 4 , In 2 MoO 4 and Tl 2 MoO 4 molecules isolated in nitrogen matrices at 12 K have been obtained. D 2d symmetry of these species is proposed. The splitting of the v 3 ( F 2 ) mode on passing from T d to D 2d symmetry is briefly discussed.

Complexes of dihydroxybenzenes with carbon monoxide by DFT calculations and FT-IR matrix spectroscopy

Abstract Weakly bound complexes of dihydroxybenzenes and nitrophenols with carbon monoxide were the objects of theoretical studies based on the Becke–Lee–Parr density functional. Stability and vibrational spectra of all stable bimolecular complexes were determined and the theoretical results were integrated by matrix isolation FT-IR spectroscopy measurements.

Some trends in the infrared spectra of matrix isolated tetrahedral ternary oxides

Abstract The splitting of the T2 stretching vibration into B2 and E modes on passing from Td to D2d symmetry is discussed for M2XO4 molecules (M = Li, Na, K, Cs, In and T1. X = Cr, Mo, W and S). Correlations between XO stretching force constants, OXO bond angles and cation polarizabilities are made.