Geometries and energy separations of low-lying states of YNH and NYH

Abstract

Complete active-space multiconfiguration self–consistent field followed by multireference configuration-interaction calculations are carried out on low-lying electronic states of YNH and NYH. We find the X 2Σ+ linear state of Y–N–H to be 55 kcal/mol more stable than the bent NYH and 59 kcal/mol more stable than the linear N–Y–H. Our calculations confirm the recent assignment of the first observed spectra generated by laser vaporization of Y metal + He/NH3. The theoretical dipole moment of the Y–N–H molecule (3.06 D) is in excellent agreement with an experimental value of 3.06 D obtained by Simard et al. The theoretical Y–N and N–H bond lengths are also in good agreement with the experimental results.