Picosecond transient Raman spectroscopy: The photoisomerization of trans-stilbene

Abstract
We measured picosecond transient resonance Raman spectra of t‐stilbene in hexane using a high repetition rate, amplified, synchronously pumped dye laser. We assign four vibrational frequencies to the olefinic moiety. Two of these frequencies, 1238 and 1565 cm1, have broad, asymmetric bands. We attribute this band shape to a distribution of excited state molecular conformers having different single and double bond strengths.