The electronic structure and conformation of dimethylaminobenzonitrile
Tóm tắt
Ab initio molecular orbital (MO) computations on the closed shell singlet ground state ofN, N-dimethylaminobenzonitrile (DMABN) are reported. Fully optimized structures of several conformers of DMABN were calculated at the HF/6-31G level of theory. Our results indicate that for each of these conformations the minimum energy structure has a trigonal (sp2 hybridized] amino nitrogen. The most stable DMABN conformer was found to be planar with its methyl groups eclipsed. The Koopmans ionization potentials and dipole moments of the various ground state conformers are compared. The implications for dynamical models of twisted-intramolecular charge transfer (TICT) are discussed. Moreover, the use of qualitative MO theory arguments provides an interpretation of the computational results in a simple orbital interaction framework.
Tài liệu tham khảo
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The computed HF/6-31G ground state energies of ec(1)-, ec(2)-, and st-DMABN are: -455.3312 a.u., -455.3359 a.u., and -455.3325 a.u. respectively. The corresponding closed shell HF/6-31G minimum energies at the perpendicular conformations are: -455.3238 a.u., -455.3221 a.u., and-455.3226 a.u. respectively
The optimum geometries of the 90°-twisted conformations of ec(1)-, ec(2)-, and st-DMABN calculated at the HF/6-31G level of theory can be obtained from the authors.
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