Crystal Structures of trans‐[Ta₆Cl₁₂(OH)₄(H₂O)₂] · 10 H₂O and (NMe₄)₂[Ta₆Cl₁₂(OH)₆] · 21 H₂O

Abstract

Abstract The compounds trans ‐[Ta 6 Cl 12 (OH) 4 (H 2 O) 2 ] · 10 H 2 O 1 , (NMe 4 ) 2 [Ta 6 Cl 12 (OH) 6 ] · 21 H 2 O 2 and Na 2 [Ta 6 Cl 12 (OH) 6 ] · 16 H 2 O 3 containing octahedral tantalum chloro clusters were isolated from alkaline methanol/water solutions of [Ta 6 Cl 12 ] 4+ . Crystal structures were solved for 1 and 2. Crystal data: 1 , monoclinic, space group P2 1 /c (No. 14), a = 938.5(2) pm, b = 1220.3(2) pm, c = 1391.7(4) pm, β = 103.87(2)°, V = 1547.5(6) × 10 6 pm 3 , Z = 2; 2 , rhombohedral, space group R 3 (No. 148), a = 1201.4(2) pm, c = 3110.8(6) pm, V = 3888.5(12) × 10 6 pm 3 , Z = 3; 3 , cubic F lattice, a = 1451(2) pm, V = 3055(13) × 10 6 pm 3 , Z = 4. The cluster in 1 contains the neutral, mixed‐coordinated trans ‐[Ta 6 Cl 12 (OH) 4 (H 2 O) 2 ] cluster with TaOH and TaOH 2 distances of 210.4(5) pm and 214.5(5) pm, respectively. One coordinated H 2 O molecule from one cluster and a coordinated OH − group from a neighbouring cluster form H 3 O 2 − intercluster bridges with the O …︁ HO distance 253.7(7) pm. Twelve TaCl (bridging) distances range from 244.1(2) to 245.2(2) pm. The structure of 2 is built of [Ta 6 Cl 12 (OH) 6 ] 2− anions, NMe 4 + cations and water molecules, the latter linked to the anions by hydrogen bonds.