TY - JOUR
T1 - Resonance-enhanced two-photon ionization mass spectroscopy of ephedrine
T2 - Indication for a state-selective fragmentation in a flexible molecule
AU - Karaminkov, R.
AU - Chervenkov, S.
AU - Härter, P.
AU - Neusser, H. J.
PY - 2007/7/17
Y1 - 2007/7/17
N2 - The vibronic structure of the S1 ← S0 spectrum of ephedrine was measured by resonance-enhanced two-photon ionization spectroscopy with mass resolution under cold molecular beam conditions. The spectra recorded at four different mass channels, m/z = 165 (parent), 58, and the hitherto unknown 71, 85 fragment ions show dissimilar vibronic fine structure and the observed mass pattern strongly depends on the selected intermediate vibrational state. This points to an intermediate state-selected process resulting in a different fragmentation mass pattern. Ab initio calculations at the MP2/6-311++G** level demonstrate that the AG (a) conformer is more stable by 238 cm-1 than the next stable GG (a) conformer.
AB - The vibronic structure of the S1 ← S0 spectrum of ephedrine was measured by resonance-enhanced two-photon ionization spectroscopy with mass resolution under cold molecular beam conditions. The spectra recorded at four different mass channels, m/z = 165 (parent), 58, and the hitherto unknown 71, 85 fragment ions show dissimilar vibronic fine structure and the observed mass pattern strongly depends on the selected intermediate vibrational state. This points to an intermediate state-selected process resulting in a different fragmentation mass pattern. Ab initio calculations at the MP2/6-311++G** level demonstrate that the AG (a) conformer is more stable by 238 cm-1 than the next stable GG (a) conformer.
UR - http://www.scopus.com/inward/record.url?scp=34347358495&partnerID=8YFLogxK
U2 - 10.1016/j.cplett.2007.05.111
DO - 10.1016/j.cplett.2007.05.111
M3 - Article
AN - SCOPUS:34347358495
SN - 0009-2614
VL - 442
SP - 238
EP - 244
JO - Chemical Physics Letters
JF - Chemical Physics Letters
IS - 4-6
ER -