Ab Initio Calculations on the Intramolecular Electron Transfer Rates of a Bis(hydrazine) Radical Cation

Electron transfer (ET) rates of a charge localized (Class II) intervalence radical cation of a bis(hydrazine) are investigated theoretically. First, the intramolecular ET parameters, i.e., reorganization energy, electronic coupling, and effective frequency, are calculated using several ab initio approaches. And then, the extended Sumi−Marcus theory is employed to predict ET rates by using the parameters obtained. The results reveal that the rates of three isomers of [22/hex/22]+, oo+[22/hex/22]+, io+[22/hex/22]+, and oi+[22/hex/22]+, are agreement with the experiment quite well while the rate of isomer ii+[22/hex/22]+ is about 1000 times larger than those of the others. The validity of different ab initio approaches for this system is discussed.