THE CHEMICAL NATURE OF INTERHALOGEN MOLECULES IN ICI AND IBR-GRAPHITE FROM I-27-MOSSBAUER AND I-129 MOSSBAUER-SPECTROSCOPY

The127I- and129I-Mössbauer resonances are applied to study the chemical nature of the interhalogen molecules ICI and IBr in stage-1 and stage-2 graphite intercalation compounds (GICs) and, for sake of comparison, in their solid molecular modifications. For both GIC systems one observes, in support of a model for the intercalate structure derived from recent X-ray absorption studies, two sites with an intensity ratio 1:1 and with similar isomer shifts and electric-quadrupole splittings. The charge transfer mechanisms are discussed in conjunction with complementary X-ray absorption and photoemission studies. © 1990 J.C. Baltzer AG, Scientific Publishing Company.