## Abstract

Standard ab initio molecular orbital theory and density functional theory calculations have been used to calculate absolute one-electron reduction potentials of several para-quinones in acetonitrile. The high-level composite method of G3(MP2)-RAD is used for the gas-phase calculations and a continuum model of solvation, CPCM, has been employed to calculate solvation energies. To compare the theoretical reduction potentials with experiment, the reduction potentials relative to a standard calomel electrode (SCE) have also been calculated and compared to experimental values. The average error of the calculated reduction potentials using the proposed method is 0.07 V without any additional approximation. An ONIOM method in which the core is studied at G3(MP2)-RAD and the substituent effect of the rest of the molecule is studied at R(O)MP2/6-311+G(3df,-2p) provides an accurate low-cost alternative to G3(MP2)-RAD for larger molecules.

Original language | English |
---|---|

Pages (from-to) | 7227-7232 |

Number of pages | 6 |

Journal | Journal of Physical Chemistry A |

Volume | 111 |

Issue number | 30 |

DOIs | |

Publication status | Published - 2 Aug 2007 |