title: Two lanthanum(III) complexes containing η2-pyrazolate and η2-1,2,4-triazolate ligands: intramolecular C-H...N/O interactions and coordination geometries.
abstract: The lanthanum(III) complexes tris(3,5-diphenylpyrazolato-κ(2)N,N')tris(tetrahydrofuran-κO)lanthanum(III) tetrahydrofuran monosolvate, [La(C(15)H(11)N(2))(3)(C(4)H(8)O)(3)]·C(4)H(8)O, (I), and tris(3,5-diphenyl-1,2,4-triazolato-κ(2)N(1),N(2))tris(tetrahydrofuran-κO)lanthanum(III), [La(C(14)H(10)N(3))(3)(C(4)H(8)O)(3)], (II), both contain La(III) atoms coordinated by three heterocyclic ligands and three tetrahydrofuran ligands, but their coordination geometries differ. Complex (I) has a mer-distorted octahedral geometry, while complex (II) has a fac-distorted configuration. The difference in the coordination geometries and the existence of asymmetric La-N bonding in the two complexes is associated with intramolecular C-H...N/O interactions between the ligands.
authors.affiliation: Applied Chemistry Department, School of Material Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, People's Republic of China.
authors.forename: Yu-Long
authors.initials: YL
authors.lastname: Wang
authors.forename: Meng
authors.initials: M
authors.lastname: Feng
authors.forename: Xian
authors.initials: X
authors.lastname: Tao
authors.forename: Qing-Yun
authors.initials: QY
authors.lastname: Tang
authors.forename: Ying-Zhong
authors.initials: YZ
authors.lastname: Shen