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A novel cobalt(II)–molybdenum(V) phosphate organic–inorganic hybrid polymer

“…As observed for some related structures [19], this building unit has a C 3 symmetry through a three-fold axis containing the geometrical centre of the moiety and perpendicular to the plane of the Mo 5+ centres. It can be found in several Mo 5+ phosphate compounds [6][7][8]18,20], and is closely related to the structure of a number of polyoxomolybdenum(V) clusters containing organophosphonate ligands [21], as sulphite [22], sulphate/arsenite [23] and carbonate groups [19]. Moreover, these complexes are structurally related to the Anderson polyoxoanions of the [XMo 6 O 24 ] nÀ type, which also show a Mo 6 planar ring with a central octahedral coordination position occupied by an heteroatom (X ¼ I, Te, Fe or Al) [24].…”

“…Hydrogen atoms associated with protonated OH bridges in the {Mo 6 O 12 (OH) 3 } moieties, as described by Se´cheresse and collaborators [18], were also not clearly visible in difference Fourier maps. Just like for the hydrogen atoms associated with the water molecules of crystallisation, no attempt was made to place these hydrogen atoms in calculated positions, but they have all been included in the empirical formula of the compound (see Table 1).…”

Self-assembly of four new extended architectures based on reduced polyoxometalate clusters and cadmium complexes

“…The [P 4 Mo 6 O 28 (OH) 3 ] 9À anion (denoted [P 4 Mo 6 ]), with various degrees of protonation is the most often encountered building unit in the reduced molybdenum phosphates. In the reported reduced molybdenum phosphates, [P 4 Mo 6 ] building units mostly were linked by alkali metal cations or first row transition metal cations to form 1D polymers or 2D and 3D microporous or tunnel materials [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21]. However, the examples of reduced molybdenum phosphates connected with transition metal complexes have rarely been reported [13,[17][18][19]21,23].…”

Structural characterizations and magnetic properties of three new reduced molybdenum phosphates

“…An important subclass of the POMs family is the reduced molybdenum phosphate based on the association of {Mo v 2 O 4 } fragments and PO 4 tetrahedra with structural range from zero to three dimensions, and in those intriguing structures [P 4 Mo 6 ] cluster units formed from {Mo v 2 O 4 } and PO 4 are firstly connected by metal-oxygen polyhedra producing M[P 4 Mo 6 ] 2 building blocks which are further linked by transition metal complexes or metal-oxygen polyhedra to result in extended structures. To our knowledge, in reported to date 38 compounds containing M[P 4 Mo 6 ] 2 building blocks there are 2 zero- [4,5], 15 one- [6][7][8][9][10][11][12][13][14][15][16][17][18], 8 two- [19][20][21][22][23][24][25] and 13 three-dimensional [9,10,14,[26][27][28][29][30][31][32][33][34] structures. It can be seen that zero-dimensional compounds containing M[P 4 Mo 6 ] 2 building unit are rare.…”

“…It can be seen that zero-dimensional compounds containing M[P 4 Mo 6 ] 2 building unit are rare. In reported compounds involving the above-mentioned structure unit, there exist a variety of sandwich atoms M including Na + [6,16,24,27], Cr III [23], Mn II [7,14,15,22,25,28], Fe II [4,[11][12][13], Fe III [20,26], Co II [8,14,18,30,31], Ni II [21,34], Zn II [10,18,19,33] and Cd II [5,9,10,29,32]. Here we report syntheses, structural characterizations, magnetic properties and photoluminescence of three new reduced molybdenum phosphates, [Co(dien) 2 ] Á (H 3 dien) 6 …”