Premium
The Cocrystallization of the Cubic [Ta 6 Br 12 (H 2 O) 6 ][CuBr 2 X 2 ]·10H 2 O and Triclinic [Ta 6 Br 12 (H 2 O) 6 ]X 2 · trans ‐[Ta 6 Br 12 (OH) 4 (H 2 O) 2 ]·18H 2 O (X = Cl, Br, NO 3 ) Phases with the Coexistence of [Ta 6 Br 12 ] 2+ and [Ta 6 Br 12 ] 4+ in the Latter
Author(s) -
Vojnović M.,
Brničević N.,
Bašic I.,
Planinić P.,
Giester G.
Publication year - 2002
Publication title -
zeitschrift für anorganische und allgemeine chemie
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.354
H-Index - 66
eISSN - 1521-3749
pISSN - 0044-2313
DOI - 10.1002/1521-3749(200202)628:2<401::aid-zaac401>3.0.co;2-y
Subject(s) - triclinic crystal system , crystallography , materials science , cubic crystal system , chemistry , crystal structure
Cubic [Ta 6 Br 12 (H 2 O) 6 ][CuBr 2 X 2 ]·10H 2 O and triclinic [Ta 6 Br 12 (H 2 O) 6 ]X 2 · trans ‐[Ta 6 Br 12 (OH) 4 (H 2 O) 2 ]·18H 2 O (X = Cl, Br, NO 3 ) cocrystallize in aqueous solutions of [Ta 6 Br 12 ] 2+ in the presence of Cu 2+ ions. The crystal structures of [Ta 6 Br 12 (H 2 O) 6 ]Cl 2 · trans ‐[Ta 6 Br 12 (OH) 4 (H 2 O) 2 ]·18H 2 O ( 1 ) and [Ta 6 Br 12 (H 2 O) 6 ]Br 2 · trans ‐[Ta 6 Br 12 (OH) 4 (H 2 O) 2 ]·18H 2 O ( 3 )have been solved in the triclinic space group P &1macr; (No. 2). Crystal data: 1 , a = 9.3264(2) Å, b = 9.8272(2) Å, c = 19.0158(4) Å, α = 80.931(1)?, β = 81.772(2)?, γ = 80.691(1)?; 3 , a = 9.3399(2) Å, b = 9.8796(2) Å, c = 19.0494(4) Å; α = 81.037(1)?, β = 81.808(1)?, γ = 80.736(1)?. 1 and 3 consist of two octahedral differently charged cluster entities, [Ta 6 Br 12 ] 2+ in the [Ta 6 Br 12 (H 2 O) 6 ] 2+ cation and [Ta 6 Br 12 ] 4+ in trans ‐[Ta 6 Br 12 (OH) 4 (H 2 O) 2 ]. Average bond distances in the [Ta 6 Br 12 (H 2 O) 6 ] 2+ cations: 1 , Ta‐Ta, 2.9243 Å; Ta‐Br i , 2.607 Å; Ta‐O, 2.23 Å; 3 , Ta‐Ta, 2.9162 Å; Ta‐Br i , 2.603 Å; Ta‐O, 2.24 Å. Average bond distances in trans ‐[Ta 6 ‐Br 12 (OH) 4 (H 2 O) 2 ]: 1 , Ta‐Ta, 3.0133 Å; Ta‐Br i , 2.586 Å; Ta‐O(OH), 2.14 Å; Ta‐O(H 2 O), 2.258(9) Å; 3 , Ta‐Ta, 3.0113 Å; Ta‐Br i , 2.580 Å; Ta‐O(OH), 2.11 Å; Ta‐O(H 2 O), 2.23(1) Å. The crystal packing results in short O···O contacts along the c axes. Under the same experimental conditions, [Ta 6 Cl 12 ] 2+ oxidized to [Ta 6 Cl 12 ] 4+ , whereas [Nb 6 X 12 ] 2+ clusters were not affected by the Cu 2+ ion.