TY - JOUR
T1 - Vibrational analysis of the inelastic neutron ascattering spectra of electron donor-acceptor complexes. II. Tetracyanoethylene-perylene by electronic structure calculations
AU - Ciezak, Jennifer A.
AU - Leão, Juscelino B.
AU - Hudson, Bruce S.
N1 - Funding Information:
The NIST Center for Neutron Research is acknowledged for providing neutron beam access on the FANS instrument. The ISIS facility of the Rutherford Appleton Laboratory is thanked for access to the TOSCA instrument. The Army Research Laboratory Major Shared Resource Center is thanked for access and support of the VASP program. An NRC Fellowship with the Army Research Laboratory partially supported J.C. during the course of this research.
PY - 2006/10/23
Y1 - 2006/10/23
N2 - The vibrational spectra of the electron donor-acceptor complex, tetracyanoethylene-perylene were measured at 4 K by inelastic neutron scattering (INS) using the filter analyzer neutron spectrometer (FANS) and at 20 K using the TOSCA instrument. A direct comparison of the measured spectrum was made to density functional calculations using the B3LYP/6-31G** treatment for the isolated complex, the PW91 pseudopotential plus plane-wave basis and the BLYP/dnd atom-centered basis solid-state methods. In general, comparisons of the observed and simulated spectra revealed that the PW91 method is slightly superior to the B3LYP/6-31G** and BLYP/dnd methods in predicting both vibrational frequency and intensity above 200 cm-1. Below 200 cm-1, the BLYP/dnd calculations gave slightly better intensity agreement. Six intermolecular vibrations were theoretically predicted with the three calculation methods and were experimentally confirmed. In addition, the molecular motions of the vibrations observed in the INS spectrum were tentatively assigned. Our calculations show that solid-state calculations are not required, at least in the case of the TCNE-perylene complex, to obtain reasonably accurate vibrational frequency information of electron donor-acceptor complexes.
AB - The vibrational spectra of the electron donor-acceptor complex, tetracyanoethylene-perylene were measured at 4 K by inelastic neutron scattering (INS) using the filter analyzer neutron spectrometer (FANS) and at 20 K using the TOSCA instrument. A direct comparison of the measured spectrum was made to density functional calculations using the B3LYP/6-31G** treatment for the isolated complex, the PW91 pseudopotential plus plane-wave basis and the BLYP/dnd atom-centered basis solid-state methods. In general, comparisons of the observed and simulated spectra revealed that the PW91 method is slightly superior to the B3LYP/6-31G** and BLYP/dnd methods in predicting both vibrational frequency and intensity above 200 cm-1. Below 200 cm-1, the BLYP/dnd calculations gave slightly better intensity agreement. Six intermolecular vibrations were theoretically predicted with the three calculation methods and were experimentally confirmed. In addition, the molecular motions of the vibrations observed in the INS spectrum were tentatively assigned. Our calculations show that solid-state calculations are not required, at least in the case of the TCNE-perylene complex, to obtain reasonably accurate vibrational frequency information of electron donor-acceptor complexes.
KW - Electron donor-acceptor complexes
KW - Inelastic neutron scattering
KW - Vibrational spectroscopy
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U2 - 10.1016/j.theochem.2006.04.037
DO - 10.1016/j.theochem.2006.04.037
M3 - Article
AN - SCOPUS:33748150496
SN - 2210-271X
VL - 767
SP - 23
EP - 28
JO - Computational and Theoretical Chemistry
JF - Computational and Theoretical Chemistry
IS - 1-3
ER -