TY - JOUR
T1 - Threshold photoelectron photoion coincidence spectroscopy sheds light on the dissociation of pyrrole and thiophene molecular ions
AU - Rennie, Emma E.
AU - Cooper, Louise
AU - Shpinkova, Larisa G.
AU - Holland, D. M P
AU - Shaw, David A.
AU - Mayer, Paul M.
PY - 2010/2/15
Y1 - 2010/2/15
N2 - Threshold photoelectron photoion coincidence spectroscopy was employed to examine the loss of ethyne from ionized pyrrole and thiophene near their dissociation thresholds as a function of internal energy and reaction time. The B3-LYP/6-311+G(3df,3pd) minimum energy reaction pathways for ethyne loss from both ions are presented. The experimental molecular ion breakdown curves were modeled with RRKM theory. For ionized pyrrole, the fitting results in confirmation of the transition state energies in the decomposition pathways. For ionized thiophene, the modeling suggests that ethyne loss is a concerted process rather than a true step-wise reaction. If so, the fitting yields a ?fH298 for CH2CS+{radical dot} of 1033 ± 2 kJ mol-1. © 2009 Elsevier B.V. All rights reserved.
AB - Threshold photoelectron photoion coincidence spectroscopy was employed to examine the loss of ethyne from ionized pyrrole and thiophene near their dissociation thresholds as a function of internal energy and reaction time. The B3-LYP/6-311+G(3df,3pd) minimum energy reaction pathways for ethyne loss from both ions are presented. The experimental molecular ion breakdown curves were modeled with RRKM theory. For ionized pyrrole, the fitting results in confirmation of the transition state energies in the decomposition pathways. For ionized thiophene, the modeling suggests that ethyne loss is a concerted process rather than a true step-wise reaction. If so, the fitting yields a ?fH298 for CH2CS+{radical dot} of 1033 ± 2 kJ mol-1. © 2009 Elsevier B.V. All rights reserved.
KW - Activation energy and entropy
KW - Density functional theory
KW - Pyrrole ion
KW - Thiophene ion
KW - Threshold photoelectron photoion coincidence spectroscopy
UR - http://www.scopus.com/inward/record.url?scp=75749107381&partnerID=8YFLogxK
U2 - 10.1016/j.ijms.2009.12.002
DO - 10.1016/j.ijms.2009.12.002
M3 - Article
SN - 1387-3806
VL - 290
SP - 142
EP - 144
JO - International Journal of Mass Spectrometry
JF - International Journal of Mass Spectrometry
IS - 2-3
ER -