title: Long-range ferromagnetic ordering in two-dimensional coordination polymers Co[N(CN)2]2(L) [L = pyrazine dioxide (pzdo) and 2-methyl pyrazine dioxide (mpdo)] with dual mu- and mu3-[N(CN)2] bridges.
abstract: Two novel coordination polymers of Co(II) with dicyanamide (dca) were obtained by the addition of ancillary ligands of pyrazine dioxide (pzdo) and 2-methyl pyrazine dioxide (mpdo) into the Co-dca binary system, respectively. Co[N(CN)(2)](2)(pzdo) (1) crystallizes in the orthorhombic space group of Pnnm (No. 58) with a = 9.4699(5) A, b = 14.9984(3) A, c = 7.4313(7) A, and Z = 4, while Co[N(CN)(2)](2)(mpdo) (2) is in the monoclinic space group C2 (No. 5) with a = 16.5391(4) A, b = 9.6065(2) A, c = 7.5001(2) A, beta = 105.779(1) degrees, and Z = 4. Both complexes contain similar two-dimensional triangular Co-dca layers, which offer rare examples of mixed 1,5-mu- and mu(3)-dca bridging coordination polymers with long-range ferromagnetic ordering below ca. 2.5 K.
authors.affiliation: College of Chemistry and Molecular Engineering, State Key Laboratory of Rare Earth Materials Chemistry and Applications, PKU-HKU Joint Laboratory on Rare Earth Materials and Bioinorganic Chemistry, Peking University, Beijing 100871, China.
authors.forename: Hao-Ling
authors.initials: HL
authors.lastname: Sun
authors.forename: Song
authors.initials: S
authors.lastname: Gao
authors.forename: Bao-Qing
authors.initials: BQ
authors.lastname: Ma
authors.forename: Gang
authors.initials: G
authors.lastname: Su