INTRINSIC AND ENVIRONMENTAL-EFFECTS IN THE STRUCTURE AND MAGNETIC-PROPERTIES OF GLYCINE RADICAL IN AQUEOUS-SOLUTION

The electron spin resonance (ESR) spectrum of the radicals derived fro m glycine in aqueous solution has not been reproduced satisfactorily u ntil now, even by refined quantum mechanical approaches. Here we will show that a recently developed computational tool provides, instead, r esults in remarkable agreement with experiment. The computational prot ocol is based on density functional calculations, on the simulation of the solvent with a continuous dielectric description, and on averagin g over the most important vibrational motions. Both the direct polariz ation and the geometry relaxation induced by the solvent on the glycin e radical are analyzed, and their effect on the ESR spectra is evaluat ed. The present procedure is able to separate the various intrinsic an d environmental contributions and to provide useful insight to the str uctural study of large flexible radicals in solution.