On optical dispersion in transparent molecular systems

Abstract

The Mössbauer data of the new molecular state of Na₂Fe(CN)₅NO · 2H₂O, generated by coherent light, were investigated, particularly as a function of temperature. Its energetic position is close to the molecular groundstate and separated from the excited electronic states by a wide gap. It is optically generated by an inelastic scattering process. The electric field gradient is solely determined by the asymmetric charge distribution of the valence electrons which have the same symmetry properties as the groundstate. The dynamics of the molecular vibrational oscillators is for the new molecular state identical with that of the groundstate. The thermal conversion of the new states, having infinite radiative lifetime, back to the groundstate is determined at elevated temperatures by a peculiar decay function which solely depends upon the internal thermal agitation of the nitroprusside molecular complex [Fe(CN)₅NO]²⁻. There is strong evidence that the new molecular state is not a high-spin state. There is no other state of the molecule known which, in terms of its physical properties, its way of generation and decay, is related to the new state reported.