title: Reversible single-crystal-to-single-crystal transformation and highly selective adsorption property of three-dimensional cobalt(II) frameworks.
abstract: A three-dimensional (3D) coordination polymer, [Co(3)(L)(2)(BTEC)(H(2)O)(2)]·2H(2)O [1, HL = 3,5-di(imidazol-1-yl)benzoic acid, H(4)BTEC = 1,2,4,5-benzenetetracarboxylic acid], with tfz-d topology has been hydrothermally synthesized. The framework of 1 has high thermal stability and exhibits single-crystal-to-single-crystal (SCSC) transformations upon removing and rebinding the noncoordinated and coordinated water molecules. X-ray crystallographic analyses revealed that the coordination geometry of Co(II) changes from octahedral to square pyramid upon dehydration, accompanying the appearance of one-dimensional (1D) open channels with dimensions of 2.0 × 2.8 Å. The dehydrated form [Co(3)(L)(2)(BTEC)] (2) exhibits highly selective adsorption of water molecules over N(2), CH(3)OH, and CH(3)CH(2)OH, which could be used as sensors for water molecules. Furthermore, the magnetic properties of 1 and 2 were investigated, showing the existence of ferromagnetic interaction between the Co(II) atoms within the trinuclear subunit.
authors.affiliation: Coordination Chemistry Institute, State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Su
authors.forename: Min
authors.initials: M
authors.lastname: Chen
authors.forename: Taka-aki
authors.initials: TA
authors.lastname: Okamura
authors.forename: Man-Sheng
authors.initials: MS
authors.lastname: Chen
authors.forename: Shui-Sheng
authors.initials: SS
authors.lastname: Chen
authors.forename: Wei-Yin
authors.initials: WY
authors.lastname: Sun