ESR spectra of Ag3(2A1) in an N2 matrix

Abstract

ESR spectra assigned to Ag3 molecules have been produced by codepositing atomic silver with excess nitrogen at temperatures close to 4.2 K. The spectra are characterized by an axially symmetric spin Hamiltonian having g∥ =1.9933(3) and g⊥ =1.9558(3) and, for 107Ag3, A∥(1) =310.8(6) G with A⊥(1) =310.1(6) G and A∥(2) =76.0(2) G with A⊥(2) =72.6(2) G for the apical(1) and basal(2) nuclei, respectively. The axial symmetry of the spectra is believed to imply that the trimer is rotating about one axis. There is no evidence for a pseudorotating trimer spectrum. The isotropic spin populations are ρ5s(1) =0.51 and ρ5s(2) =0.12 implying an acute angled geometry with ground state symmetry 2A1. This is in sharp contrast to the obtuse angled isomer (2B2 ground state) found for Ag3 in a C6D6 matrix. For Ag3(2A1) there is little p character on the apical atom but a 10%–15% p hybridization on each of the two basal nuclei.