A general study of the spin population of alpha-nitronyl nitroxide radicals: radicals with crystals presenting dominant ferro or antiferromagnetic behavior

The atomic spin population of all the alpha -nitronyl nitroxide radicals wh ose crystals present dominant ferro or antiferromagnetic properties is comp uted at the B3LYP/6-31G(d) level, searching for changes and similarities in their spin distribution. The quality of the computed values is previously tested on the alpha -phenyl-nitronyl nitroxide radical using various basis sets. It is found that computed atomic spin population presents small chang es with the basis set, when the computation is done using the B3LYP density functional. The B3LYP/6-31G(d) atomic spin population of the radicals pres enting dominant ferromagnetic interactions is practically independent of th e system. The same is true for the antiferromagnetic systems. The two sets present also similar values. This fact is of great help when analyzing the magnetic properties of the crystals of these radicals. (C) 2001 Elsevier Sc ience B.V. All rights reserved.