Rotational Analysis of the Tantalum Oxide Bands

Abstract

BANDS of the tantalum oxide molecule have been photographed in the ultra-violet and the visible regions on a 21-ft. concave grating in the Department of Physics, University of Stockholm, in the first order, giving a reciprocal dispersion of about 1.2 A./mm. The previous analyses¹ are found to be incorrect. The revised analysis shows that the bands in these regions can be divided into two systems A and C. Bands of system C consist of two sub-systems with their (0,0) bands at vv24064 and 23348. Rotational structure of the (2,0), (3,1), (1,0), (2,1), (0,0) and (0,1) bands of system A, (1,0) and (0,0) bands of the sub-system v24064 and (1,0), (0,0) and (0,1) bands of the other sub-system of C has been analysed. Bands of system A show only two branches each and are ascribed to the transition c²Δ_3/2–α²Δ_3/2. Strong Q branches are very prominent in all the bands of system C. Large Λ-type doubling is observed in the upper state levels and is found to vary linearly with J in the sub-system v23348. The bands are ascribed to the transition b²Π-α²Δ. All three states involved belong to Hund's coupling case (α). The vibrational and rotational constants obtained are given in Table 1.