抄録
The dynamics of electronic dynamics of precursor of vitamin D3, 7-dehydrocholesterol (7-DHC), is investigated
by deep ultraviolet (DUV) transient absorption spectroscopy using 11 fs pulses. The electronic
transition energy is modulated by vibrational modes having frequencies of 1183, 1347, 1459, 1603,
and 1766 cm‒1. The most pronounced frequency feature is a shift of the central frequency from 1615 to
1603 cm‒1, which is discussed in terms of excited state depopulation of 7-DHC. We report the absorption
spectra of 1B2 excited state of 7-DHC and cZc-previtamin D3 (czc-Pre) generated through the ring
opening in 7-DHC calculated on the basis of kinetic analysis of transient absorbance changes.
