modes of (de)oxyheme of hemoglobin as obtained from three colour CSRS.

ABSTRACT We report polarisation sensitive Coherent Stokes Raman Scattering (CSRS) measurements of oxy- and deoxyhemoglobm in aqueous solutions that were carried out under electronic resonance with the Q absorption bands. All independent susceptibility Xt'3' components as well as anisotropic and anti-symmetric scatteringcontributions were resolved within frequency non degenerate CSRS scheme. Eight bands of oxy- and five of deoxyhemoglobin were observed in the range 1500-1680 cm1. Each set of dispersion profiles was simultaneouslyfitted with a set ofparameters including band positions, widths, amplitudes, phases and, importantly, all the CSRSdepolansation ratios. On this basis the major bands were assigned to non-totally symmetric v10, v11 and v19 modesofthe porphyrin macrocycle. These displayed a clear correlation ofvibrational phase with the mode symmetry. Of eight bands resolved in oxyHb spectra three were attributed to features of intermediate deoxyHb, caused by a partial photolysis of oxyhemes. On a nanosecond time scale they were found essentially similar to those found for