Reactions of Laser-Ablated U Atoms with HCN: Infrared Spectra in Solid Argon and Quantum Chemical Calculations for HUNC

Abstract

Reactions of laser-ablated U atoms with HCN produce HUNC, which is identified from its argon matrix infrared spectrum of strong N-C and U-H stretching modes at 2028 and 1417 cm-1. B3LYP calculations show that the unobserved HUCN isomer has a 6.3 kcal/mol higher energy, and its C-N stretching mode is about 125 cm-1 higher with more than an order of magnitude weaker intensity. Complementary experiments were done with thorium and group 4 metal atoms to form the analogous HMNC species for comparison and to demonstrate metal dependence for these new metal-bearing product absorptions.