Temperature and Time-resolved XANES Studies of Novel Valence Tautomeric Cobalt Complex

VT transition from the high-spin CoII to low-spin CoIII state was observed for complex (N-cyclo-hexyl-2-iminopyridine)(3,6-di-tert-butyl-o-benzosemiquinonato)(3,6-di-tert-butyl-catecholato)cobalt in both solid and liquid form. For the first time we demonstrate a low-temperature nanosecond pump-probe XANES experiment revealing the valence tautomeric transition in a solution of Co complex. Reversible transition was induced both under the temperature and laser radiation stimuli. We assembled a flow-through cooling system and measured pump-probe nanosecond K-edge X-ray absorption near-edge structure to observe excited-state relaxation dynamics of valence tautomeric complex (N-cyclo-hexyl-2-iminopyridine)(3,6-di-tert-butyl-o-benzosemiquinonato)(3,6-di-tert-butyl-catecholato)cobalt. Obtained results showed that for this complex reversible transition can be induced both under the influence of temperatures and laser radiation.