Infrared spectra of K2[RuCl5NO] in two excited metastable states and the evidence for the NO linkage photoisomerization of metastable state I (MSI) in [RuX5NO]2- (X=Cl,CN)

J. A. GUIDA; M. A. RAMOS; O. E. PIRO; P. J. AYMONINO

Journal of Molecular Structure

Elsevier

Año: 2002 vol. 609 p. 39 - 46

Low temperature IR vibrational spectra of light induced metastable states I and II (MSI and MSII) of K2[RuCl5NO] are presented and discussed here: MSII bands and some MSI features are reported for the first time. Some of the MSI bands confirm Raman spectroscopic observations. The thermal deactivation of MSI and MSII states occur at temperatures T(MSI)>T(MSII). This is the same ordering observed for Na[Fe(CN)5NO].2H2O and certain RuNO complexes but opposite to that found for Na2[M(CN)5NO].2H2O (M=Ru, Os). Evidence for RuON structure of MSI is provided for [RuL2NO]-2 (L=CN, Cl) as results of the analysis of nu(NO) differences between 15/14N(16O) and 18/16O(14N) pairs of natural isotopic compositions.