Rotational analysis of the A0+, B0+ ← X 1Ʃ+ systems of gaseous AgF

The absorption spectrum of AgF in the region 300.0 to 355.0 nm consists of a continuum centred at about 303.0 nm and two-band systems, A0+, and B0+ ← X 1Ʃ+. Rotational analyses have been made for all seven bands observed in the A─X system and of four bands in the B─X system, for both 107AgF and 109AgF. State A seems to have a very low dissociation energy and may possess only two stable vibrational levels. Lines at high J appear diffuse, indi­cating predissociation, perhaps by rotation. State B is also predissociated and only the bands with v' ═ 0 show sharp rotational structure. The predissociating state is probably an Ω ═ 1 state which is the upper state of the 303.0 nm continuum. Constants for the ground state of 107AgF are as follows: Gv ═ 513.447 ± 0.009 (v + ½) ─ 2.593 ± 0.002 (v + ½)2 Bv ═ 0.26567 ─ 0.001901± 8 (v + ½).