Super-exchange and hopping mechanisms and distance dependence of long-range electron transfer (ET) and charge transfer (CT) in pa-(gly)(n=0-6)-aa (pa = C6H4(CO)(2)N-(CH-2CO), gly = glycine, aa = HNCH2COOCH3) ionic molecules have been explored by computational studies of ET matrix element V-PS, ET rate constant k(ET) and reorganization energies using two-state variational method (TSVM) and classical and semi-classical rate models. For comparison electron correlation effects are examined in the calculations. Calculated distance dependences of k(ET) are in good agreement with the experimental predictions. These results are then used to elucidate ET and CT reaction mechanisms. (c) 2006 Elsevier B.V. All rights reserved.