G. Edvinsson

A low-lying Ω = 2 state in the ThO molecule

Abstract A new, low-lying excited state called Q with Ω = 2 has been found in ThO. Analyses of transitions from previously known excited states to this Q state have made it possible to accurately relate the G , H , O , and P states to the ground state XO . The molecular constants (cm −1 ) obtained for the Q state are T 0 , 6127.92; ω e , 858.42; ω e χ e , 2.29; B e , 0.32703; α e 0.00133; and D 0 , 1.919 × 10 −7 .

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.

Rotational analysis of some violet and green bands in the ThO spectrum

Abstract Four new systems in the ThO spectrum have been rotationally analyzed. Going to increasing wavelengths they are designated U-X, Y-W, U-H, and Z-Q. U, Y, W, and Z are new electronic states. They have Ω = 1, 2, 3, and 2 , respectively. X is the ground state with Ω = 0 + ; H and Q are previously known states having Ω = 1 and 2 . In the Z-Q system the 0-0 and 1-1 bands are treated, in the others only the 0-0 bands are treated. The vibrational numbering of the Y-W band is somewhat doubtful; it might be the 0-1 band and not the 0-0 band. The Y and W states can not be placed in the term scheme. Perturbations in the U state are discussed. The molecular constants for the new states are given.

On the spectrum of YCl. rotational analyses of the C1Σ+-X1Σ+, D1Π-X1Σ+ and J1Π-X1Σ+ band systems

Thermal emission and absorption spectra of the YCl molecule have been studied in high resolution using a Fourier transform spectrophotometer and a 5-m Fastie spectrograph. Band systems of the C1Σ+-X1Σ+, D1Π-X1Σ+ and J1Π-X1Σ+ transitions have been rotationally analyzed. Accurate molecular constants have been determined.

Two band systems of ThO in the near ultraviolet

Two new band systems in the near ultraviolet region of the ThO spectrum have been rotationally analyzed. The corresponding transitions are designated A′(0+)-X(0+) and B′(Ω = 1)-X(0+). Molecular constants for the new electronic states A′ and B′ are given.

On the emission spectrum of HfS

The microwave induced emission spectrum of gaseous HfS has been studied in the region 11 000-21 000 cm−1. Six band systems, not previously observed, have been photographically recorded in grating spectrographs and rotationally analysed. Five of the transitions terminate on a common lower state, the X1Σ state. The five upper states are in energy order the A1Σ, B1Π, D1Π, E1Π and F1Σ states. The sixth system, located between the B-X and D-X systems, is perturbed and is identified as the sulphide counterpart to the hafnium oxide system called C. Also, the three analysed lowest vibrational levels of the F1Σ state are perturbed. Accurate molecular constants of the five regular states, the X, A, B, D, and E states, have been determined using the direct approach method. Only the most abundant isotopomer Hf180S32 is treated.