ИСТИНА

Formation enthalpies in a gas phase of 3-methyl-4-nitrofurazan and of some biphenyl derivatives are determined. The calculation scheme by a method of "a double difference" of enthalpies of formation of aromatic radicals and bond dissociation egergies is offered. The new calculation method allows exclude the energies of reorganization of molecules fragments into radicals and to determine the enthalpies of formation of radicals and energies of disociation of chemical bonds by enthalpies of atomization. Enthalpies of formation of 3- methylfurazan-4-yl and biphenyl-4-yl are determined.