New Inorganic−Organic Hybrid Materials Based on Polyoxovanadates: [Morp]6[VO4⊂V14O32(OH)6]·2H2O, [Morp]VO3, [HMTA-CH3]4[H2V10O28]·5H2O, and [HMTA-H][HMTA-CH2OH]2[H5V10O28]·6H2O

Four new organic−inorganic hybrid materials containing oxovanadate clusters have been synthesized from acidified, aqueous vanadate solutions in the presence of organic templates morpholine or hexamethylenetetraamine and their crystal structures are reported. Crystal data: [Morp] 6 [V V O 4 ⊂V IV 3 V V 11 O 32 (OH) 6 ]·2H 2 O ( 1 ) (Morph = morpholinium), monoclinic, space group C 2/ c, a = 19.2521(9), b = 14.1317(6), and c = 21.3212 (9) Å, β = 92.117(10)°, V = 5796.8(4)(Å) 3, and Z = 4; [Morp]VO 3 ( 2 ), monoclinic, space group P 2 1 / c, a = 6.4775(7), b = 20.099(2), and c = 5.7999(6) Å, β = 105.682(2)°, V = 726.99(13) Å 3, and Z = 2; [HMTA-CH 3 ] 4 [H 2 V 10 O 28 ]·5H 2 O ( 3 ) (HMTA = hexamethylenetetramine), monoclinic, space group C 2/ m, a = 20.8504(6), b = 8.6955(3), and c = 13.4096(4) Å, β = 124.369(1)°, V = 2006.78(11) Å 3, and Z = 2; and [HMTA-H][HMTA-CH 2 OH] 2 [H 5 V 10 O 28 ]·6H 2 O ( 4 ), orthorhombic, space group Pna 2 1, a = 23.4579(2), b = 19.1436(3), and c = 11.0369(2) Å, V = 4956.33(13) Å 3, and Z = 4. The formation of novel inorganic−organic hybrid compounds in the presence of organic bases under significantly different reaction conditions such as pH, nature of templates, and starting materials are discussed.