LaMo8O14

Thermoelectric properties of molybdenum oxides LnMo8O14 (Ln = La, Ce, Pr, Nd and Sm)

“…Molybdenum oxides with the formula LnMo 8 O 14 (Ln = La, Ce, Pr, Nd and Sm) [16,17,[29][30][31][32] were reported to contain Mo 8 clusters. LaMo 8 O 14 and CeMo 8 O 14 crystallize in the orthorhombic crystal system with the space group Pbcn as determined by the single crystal X-ray diffraction, although there is another different modification obtained from fused-salt electrolysis for LaMo 8 O 14 [16].…”

“…The densities of states (DOS) for this compound have been described elsewhere [34], so only the band structure results will be discussed here. Since all atomic sites in the structure of LaMo 8 O 14 are fully occupied, the model of this compound chosen for the calculation was taken directly from the single crystal structure determination [17] with the Pbcn symmetry. The calculated electronic band structures of LaMo 8 O 14 are shown in Fig.…”

“…Molybdenum oxides, such as LaMo 8 O 14 [16,17], LaMo 5 O 8 [18,19], Y 4 Mo 4 O 11 [20], Pr 4 Mo 9 O 18 [21] and La 5 Mo 32 O 54 [22] containing different Mo clusters with strong metal-metal bonds between the Mo atoms, are usually semiconductors with narrow band gaps, which could be potential materials for thermoelectric applications. In this work, we will introduce a series of new ntype oxides (LnMo 8 O 14 , Ln = La, Ce, Pr, Nd and Sm) containing Mo 8 clusters showing promising thermoelectric properties.…”

SmMo8O14

“…The single-crystal structures of the first four members of the series of compounds RMo8O14 (R = La, Ce, Pr, Nd) have been presented in recent papers. These compounds can be synthesized either by solid-state reaction for R = La, Ce, Pr, Nd (Kerihuel, Tortelier & Gougeon, 1996;Kerihuel & Gougeon, 1995a,b;Gougeon & Mc-Carley, 1991) or by fused-salt electrolysis in the case of LaMo8-xO14 (x = 0.0 and 0.3) (Leligny, Led6sert, Labb6, Raveau & McCarroll, 1990;Leligny et al, 1993). The main metallic building block in all these compounds is the bi-face-capped Mo8 octahedron which exists in two of the three possible isomeric forms.…”

“…These two compounds crystallize in the space group Aba2 with the following parameters: aLa = 9.196(1), bt.a = 9.985 (1), CLa = 11.171 (1) oA; and = 9.209 (3), bNd = 10.008 (2), CNd = 11.143 (4) A. In the LaMosOi4 compounds synthesized by solid-state reaction (Kerihuel et al, 1996) and in CeMosOl4 (Kerihuel & Gougeon, 1995a), the cis isomer coexists in an ordered way in equal proportion with the trans biface-capped MoB cluster. Both compounds crystallize in the orthorhombic space group Pbcn [a = 9.2065 (4), b = 11.1298(9), c = 20.0264(8)A for LaMosO H and a = 9.1937(7), b = 11.121(1), c = 20.014(1)A for CeMo8Ol4].…”