The synthesis and crystal structures of two-dimensional coordination polymers of Ph2P(O)-CH2CH2-P(O)Ph2 and Ph2P(O)-C5H3N-P(O)Ph2 with praseodymium.

Reactions of Pr(NO3)3 with Ph2P(O)-CH2CH2-P(O)Ph2 and Ph2P(O)-C5H3N-P(O)Ph2 yielded layered network coordination polymers with bidentate ligands spanning the lanthanide atoms in a bridging fashion. The praseodymium cations with "spacer" ligands form two-dimensional building blocks assembling into either square grid or herringbone network.

Commensurate and incommensurate structures of the hexabromotellurate(IV) bis[dibromodiselenate(I)] ion - [(C2H5)n(C6H5)4-nP]2[TeBr6(Se2Br2)2], n = 0,1.

Structure analysis of [(C(2)H(5))(n)(C(6)H(5))(4-n)P](2)[TeBr(6)(Se(2)Br(2))(2)] is presented for n = 1 and 0 [hereafter (I) and (II)]. Crystal (I) has been synthesized from elemental selenium, tellurium tetrabromide, ethyltriphenylphosphonium bromide and bromine. It has a standard monoclinic structure, space group P2(1)/c, and has been solved and refined to R = 0.