NEW MEASUREMENTS ON THE A^lΠ ↔ X¹Σ BAND SYSTEM OF AlH

Abstract

The AlH band system at 4241 Å was produced in a large King Furnace and the bands were photographed in emission and absorption in the second and third orders of a 21 ft. concave grating. The vibrational and rotational constants were newly determined with improved accuracy.

Emission Spectroscopy of AlH: the X¹Σ⁺, A¹Π and C¹Σ⁺ States Characteristics

“…The excited states main rotational constants agree well with the previous experimental results [8,10,12,13]. For example, our B 0 = 6.388805(51) cm −1 constant of C state compares with values of 6.393 cm −1 [8] and 6.3870 cm −1 [10].…”

“…D 1 , H 1 ) differ from those of work [13], and are closer to the results obtained by Zeeman and Ritter [12]. For example, our D 1 = 11.145(27) × 10 −4 cm −1 constants in comparison with the values 11.195 0 × 10 −4 cm −1 [12] and 11.45(11) × 10 −4 cm −1 [13], respectively.…”

“…The hypothesis of the B 1 Σ − state existence, suggested by Holst was refuted by Zeeman and Ritter [12]. The part of the band spectrum with the characteristic head in the Q branch is presented in Fig.…”

“…The main equilibrium rotational constants (B e , D e ) of the A 1 Π and C 1 Σ + states can be compared with the available results of previous experimental work [12,13] and [8], respectively. Our B e = 6.386416(43) cm −1 constant of A state agrees well with those of Zeeman and Ritter [12] of B e = 6.3868 8 cm −1 and Ram and Bernath [13] of B e = 6.38632 (14) cm −1 , respectively.…”

“…The A 1 Π -X 1 Σ + transition has been the most extensively investigated system for many years. The most comprehensive investigation of this electronic transition was provided by Zeeman and Ritter [12]. They reported on the analysis of nine bands with v = 0, 1 in the A 1 Π state and v = 0, 1, 2, 3, 4 in the X 1 Σ + state.…”