The influence of vibration-rotation interaction on intensities in the electronic spectra of diatomic molecules II. The silver hydride molecule

Abstract

The highly perturbed spectra of the A 1 E - X 1 E systems of the silver hydride and deuteride molecules are explained in terms of an anomalous rotationless potential curve for the A state. While this curve will explain the irregularity of the vibrational interval it is necessary to include the rotational energy term U(r) J = U(r) 0 + (8π 2 /μ) J ( J + 1)/ r 2 , in order to explain the intensity distribution. The potential curves derived have meaningful quantum numbers, in direct contrast to the explanation of Gerö & Schmid (1943). The perturbation is due to the interaction between the 1 E states formed by addition of a hydrogen atom to the 2 P and 2 D configurations of the silver atom. The dissociation energies of other silver-containing diatomic molecules are discussed. A partial analysis of the AgD spectrum yields the following constants in cm -1 : X 1 E + G (v) = 12500.9(v + 1/2) - 17.2(v + 1/2) 2 + 0.15(v + 1/2) 3 - 0.025(v + 1/2) 4 , B (v) = 3.258 -0.073(v + 1/2), D (v) = 8.2 x 10 -5 ; A 1 E + G (v) = 29911.3+1101.5(v+1/2)-40.7(v+1/2) 2 -1.8(v+1/2) 3 , B (v) = 3.163 - 0.124(v + 1/2) - 0.0038(tv+1/2) 2 , D (v) = 9.0 x 10 -5 + 1.7 x 10 -6 (v + 1/2); where the constants for the A state are only valid for v < 5, J < 25, as the violent perturbation observed in the hydride is again present.