L Klynning

The Band Spectrum of N2

Twenty-five bands of the First Negative System, B 2Σu+ - X 2Σg+, of the Nitrogen Molecule Ion N2+ have been analysed or reanalysed. The previous analysis of the (7, 10) band is found to be incorrect. Molecular constants for the X 2Σg+, A 2Πu, B 2Σu+ and C 2Σu+ states obtained with the term value approach from seventy-one bands are presented.

Rotational Analysis of the A-X and B-X Band Systems of CaH

The absorption spectrum of CaH in the region 6 130-7 125 A has been generated using a King furnace. The spectrum was recorded photographically in a 10.685 m concave grating spectrograph. Ten bands belonging to the A2Π-X2Σ and B2Σ-X2Σ systems have been rotationally analyzed. Perturbations between the two excited states have been observed. Computer methods have been used to calculate term values and to evaluate molecular constants.

Laser Spectroscopic Investigations of CaCl

Laser excitation and fluorescence spectra of the A2Π–X2Σ transition of gaseous calcium chloride have been observed and analyzed. Traditional absorption spectra were also recorded in a high-resolution spectrograph. Totally 1949 rotational lines were used in the calculations and the following molecular equilibrium constants (cm-1) were determined by least squares methods. The numbers in parentheses represent one standard deviation in the last digit

Laser Spectroscopic Investigations of CaCl. II. Rotational Analysis of the B2Σ- X2 Σ Transitions

Diatomic calcium chloride has been examined by means of laser excitation and fluorescence spectroscopy. A small resistance furnace and a c.w. Rhodamine 6G dye laser were used to produce the spectra. The absorption spectrum of CaCl was also recorded by using a 5 m Jarrel Ash spectrograph. The following rotational and vibrational constants of the B2Σ and X2Σ states have been derived (cm-1): B2Σ+ X2Σ+ Te 16 856.684(4) 0.0 ωe 367.196(6) 370.201(1) ωexe 1.524(2) 1.3732(1) ωeye 8.6(2) × 10-3 9.3 × 10-3 ωeze -3.8(2) × 10-4 -4.8(2) × 10-4 Be 0.154 704(1) 0.152 233 αe 8.835(3) × 10-4 7.92 × 10-4 De 1.1409(4) × 10-7 1.068 × 10-7 γe -6.531(7) × 10-2 1.38 × 10-3 γD 1.36(6) × 10-7 0.0 αγ -4.0(6) × 10-4 0.0 The figures in parentheses stand for one standard deviation in the last digit for the computed quantity.

Polarization Effects in Gaseous Calcium Chloride

The Ca+(3d2D) polarizabilities are evaluated by fitting a model of a polarizable ion pair to the experimental results of the low lying electronic states in CaCl. The Ca+(2D) polarizabilities are found to be α = 5.10 A3, αΣ = 4.16 A3 and αΔ = 0.6 A3. From these new data the location of the so far unobserved 2Δ state in CaCl is estimated to Te = 21 000 cm-1. Molecular static dipole moments, induced dipole moments, electronic structures and transition moments are thus evaluated as a function of internuclear distance for CaCl and are found to well represent the behaviour of the other Ca-halides as well. Finally the lifetimes of the A, B and C states of the Ca-monohalides are derived.

On the Λ-type Doubling in the Ground State of SiH

The (0, 0) band of the 2?-2? transition of SiH has been remeasured from high-dispersion plates and more precise values of the ?-doubling parameters for the 2? state have been determined. From these optical measurements the transition between the two components of the lowest rotational level can be predicted to lie at 2968 ? 6 MHz.

Fourier transform spectroscopy of LaCl: rotational analyses of the infrared band systems

Thermal emission spectrum of the LaCl molecule has been observed for the first time, the spectrum has been studied in high resolution using a Fourier transform spectrophotometer. Two singlet and two triplet band systems in the infrared region have been rotationally analyzed. The two singlet systems centered at 5958 cm−1 and 9557 cm−1 are shown to have a common lower state and are characterized as 1Π–1Σ and 1Σ–1Σ transitions, respectively. The common lower state is probably the ground state X1Σ+ in analogy with LaF [13] and YCl [11]. The two triplet systems centered at 7250 cm−1 and 10 650 cm−1 also have a common lower state and are here designated as 3Φ–a3Δ and 3Δ–a3Δ transitions, respectively. Molecular constants for the involved states have been determined.

On the spectrum of YCl: Rotational analysis of the B1Π-X1Σ band system

Abstract The spectrum of the YCl molecule has been studied in high resolution. A strong band system in the near infrared region has been found for the first time. This band system corresponds to the theoretically predicted B 1 Π- X 1 Σ transition. The band system has been recorded in thermal emission in high resolution using a Fourier transform spectrophotometer. Twelve bands belonging to this band system have been rotationally analyzed. Accurate molecular constants for the X 1 Σ and B 1 Π states have been determined.

On the Interaction Between the A2 Π and B2 Σ States of the CaCl Molecule

A deperturbation of the interaction between the A 2Π and B 2Σ states in CaCl is presented. The results are used to determine the mixing coefficients in a 4p, 3d, 4f Ca+ orbital hybridization model for the low lying electronic states in CaCl. These mixing coefficients are used in the interaction calculation to predict the equilibrium energy of the hitherto unobserved 2Δ molecular state. The mixing coefficients obtained are close to the ones predicted from the model of polarizable ions where the A and B states correlate to the Ca+ (2D) + Cl- (2S) states of the separated ions.

Observations of Two Photon Absorption in Gaseous CaCl. A Study of the D 2Σ and X 2Σ States

In the wavelength region, 616-623 nm, two photon processes have been observed in diatomic calcium chloride. The D 2Σ-X 2Σ transitions of both Ca35Cl and Ca37Cl were obtained. Rotational and vibrational constants have been derived for the D 2Σ and X 2Σ states of Ca35Cl.