SYNTHESIS AND CRYSTAL STRUCTURE OF HEXA(μ-TRIFLUOROACETATO)TETRAKIS(TETRAMETHYLENE SULFOXIDE)DILANTHANUM(III) POLYMER AND TETRA(μ-TRIFLUOROACETATO)BIS(TRIFLUOROACETATO)TETRAKIS(TETRAMETHYLENE SULFOXIDE)DINEODYMIUM(III)