作者:David M.L Goodgame、David A Grachvogel、Izhar Hussain、David J Williams
DOI:10.1016/s0020-1693(99)00568-x
日期:2000.4
It is shown by X-ray structural studies that the bisamide ligands N,N'-p-xylylenebisacetamide (PXBA, I), N,N'-trans-1,4-cyclohexylaminebisacetamide (1,CCHBA, II) and N,N'-trans-1,4-cyclohexylaminebis-n-butyramide (1,4-CHBB, III) form polymeric network structures with lanthanide(III) nitrates. In the compound Er-2(PXBA)(3)(NO3)(6) (1) the erbium atoms are nine-coordinate and are linked by PXBA bridges to form sheets of contiguous 78-membered metallacyclic rings. In Ce(1,4-CHBA)(2)(NO3)(3) (2) the cerium atoms are ten-coordinate and the 1,4-CHBA ligands bridge adjacent cerium centres to form sheets of contiguous 44-membered rings with (4,4) topology and with a very compact stacking of the adjacent sheets. In Nd(1,4-CHBB)(2)(NO3)(3) (3) the neodymium atoms are eight-coordinate with the 1,4-CHBB ligands also bridging adjacent neodymium centres to form sheets of contiguous 44-membered rings with (4,4) topology, but with a pronounced 'square-wave' corrugation and crest-in-trough sheet stacking. (C) 2000 Elsevier Science S.A. All rights reserved.