Rotational analysis of the A-X and B-X systems of AuBe and AuMg

Abstract

Electronic band systems of the gaseous molecules AuBe and AuMg may be observed in thermal emission or in absorption at temperatures around 2000 °C. The rotational analysis of bands of two systems of each molecule has been carried out. The ground states are 2 Σ + states, correlating with Au 2 S 1/2 and Be 1 S 0 or Mg 1 S 0 . The upper states are Ω = 1/2 states derived from Au 2 D 2 1/2 and Be 1 S 0 or Mg 1 S 0 . All the upper states show appreciable Ω-doubling. The following constants (cm-1) have been obtained: state Too A(7j Be 10® a re (A-) (i) AuBe Bh 18956-68 622-28 0-47944 4-34 2-0199 A$ 17194-88 647-57 0-49264 4-63 1-9927 X*E+ 0 600-63 0-46074 4-00 2-0605 (ii) AuMg B 19507-52 — [0-14043] — [2-3695] Ah 18409-05 — [0-14201] — [2-3562] X 2E+ 0 306-10 0-13214 0-73 2-4427 Figures in parentheses refer to v = 0. The vibrational levels in the upper states of AuBe converge rather rapidly, but only a rough estimate of the dissociation energy can be obtained: this is D 0 0 AuBe) ~ 67 kcal/mole.