Influence of alkali metal and ammonium cations on the structure of iron(II) and cobalt(III) hexacyanide complexes encapsulated in faujasite

Changing the cation composition (Na⁺ to K⁺, NH₄ ⁺ Cs⁺) of faujasite with hexacyanoferrate(II) encapsulated in the large pores causes distortion of the octahedral symmetry of the complex.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 30, No. 5, pp. 293–297, September–October, 1994.     

New inclusion compound — copper(II) hexacyanoferrate in faujasite

The copper(II) hexacyanoferrate lattice is formed within the zeolite when CuSO₄ reacts with hexacyanoferrate (II) encapsulated in faujasite under hydrothermal conditions. A quantity, of Cu²⁺ in excess of that necessary for ion exchange has an important role in forming the three dimensional structure, apparently through interactions with the zeolite skeleton. Formation of the hexacyanoferrate is accompanied by considerable deformation of the faujasite skeleton.L. V. Pisarzhevskii Institute of Physical Chemistry, Ukraine National Academy of Science, Ukraine, 252039 Kiev, Nauki Prospekt 31. Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 32, No. 1, pp. 43–46, January–February, 1996. Original article submitted April 27, 1995.     

Formation of Transition Metal Cyanoferrates in Mesoporous Molecular Sieves of the MCM-41 Type

It is shown that formation of fragments of the structures of massive transition metal cyanoferrates in mesoporous molecular sieves of MCM-41 type containing high aluminum content does not cause important changes in the porous structures of the inclusion compounds.     

High-resolution 27Al NMR study of the states of aluminum atoms in modified natural mordenite

High-resolution ²⁷Al NMR has been applied to the states of aluminum in modified natural mordenite. Acid treatment of the natural mordenite and heat treatment of the ammonium form alter the coordination state of 6–8% of the aluminum atoms from tetrahedral (in the framework) to octahecral (at the inner surfaces of the zeolite cavities). In that state, the aluminum can exchange with Na⁺, NH₄ ⁺, and other cations. This change in coordination state should have a considerable effect on the catalytic parameters of zeolites.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, No. 2, pp. 241–244, March–April, 1987.     

Peculiarities of cyanide-faujasite systems incorporating transition metal ions

Fragments of the corresponding hexacyanoferrates are formed when transition metal ions replace Na⁺ in faujasite containing hexacyanoferrate(II) encapsulated in the large pores.Translated from Teoreticheskaya i Èksperimental'naya Khimiya, Vol. 30, No. 6, pp. 332–336, November–December, 1994.