CONSISTENT CHANGES OF X-RAY PEAK PROFILES AND MOSSBAUER AREA FRACTIONS ASSOCIATED WITH HYSTERESIS OF THE SPIN-STATE TRANSITION IN [FE(4,7-(CH3)2-PHEN)2(NCS)2]

Distinct and different peak profiles of X-ray diffraction are found for the 5T2 and 1A1 phases at the high-spin (5T2) = low-spin (1A1) transition in [Fet4.7-tCH3)2-phen)2(NCS)2] (phen = 1.10-phenanthroline). Intensities of the lines show the same temperature dependence and the same hysteresis behaviour as the 5T2 and 1A1 fractions determined on the basis of Mössbauer effect. Evidence for a simultaneous change of the electronic spin state and of the crystallographic properties associated with domains of the solid is presented. © 1979.