Divalent samarium compounds with heavier chalcogenolate (EPh; E = Se, Te) ligands

Crystalline coordination complexes of Sm(EPh)(2) (E = Se, Te) are described . The selenolate compound Sm(SePh)(2) is unstable in solution, but a divale nt selenolate can be prepared and isolated when precisely 1 equiv of Zn(SeP h)(2) is present to form heterometallic [(THF)(3)Sm(mu(2)-SePh)(3)Zn(mu(2)- SePh)](n) (1). This compound is a 1D coordination polymer with alternating Sm(II) and Zn(II) ions connected by an alternating (1,3) number of bridging selenolate ligands and three THF ligands bound to each Sm(II) ion. The tel lurolate Sm(TePh)2 forms a stable pyridine coordination compound (py)(5)Sm( TePh)(2) (2) that is isostructural with known Eu and Yb benzenetellurolates . Both compounds were characterized by conventional spectroscopic methods. Polymer 1 was characterized by low-temperature single-crystal X-ray diffrac tion, and the unit cell of the tellurolate was determined. Crystal data (Mo K alpha, 153(5) K) are as follows. 1: monoclinic space group P2(1), a = 10 .666(2) Angstrom, b = 16.270(3) Angstrom, c = 12.002(3) Angstrom, beta = 11 4.81(2)degrees, Z = 2. 2: orthorhombic space group Phca, with a = 13.865(3) , b = 16.453(5) Angstrom, c = 31.952(7) Angstrom, Z = 8.