Dehydration process in recently synthesized porous inorganic salts containing water molecules and formed by large cluster anions [Re-6 X-8(CN)(6)](4-) (X= S, Se) and transition metal cations has been investigated. Desolvation process of the complex Co(DMF)(6)[Mo6Br8(NCS)(6)] containing cluster Mo anions and cations with dimethylformamide (DMF) molecules has been studied. CoK, MoK and ReL3 XAFS measurements of these new complicated compounds. before and after annealing in vacuum at the temperature of up to 250 degreesC. were performed. Changes of electronic and spatial structure of these compounds after the heat treatment have been established. and adequate structural models of the amorphous compounds obtained are suggested and discussed.