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CoCl2 is trigonal omega-like structured and crystallizes in the trigonal R-3m space group. The structure is two-dimensional and consists of three CoCl2 sheets oriented in the (0, 0, 1) direction. Co2+ is bonded to six equivalent Cl1- atoms to form edge-sharing CoCl6 octahedra. All Co–Cl bond lengths are 2.43 Å. Cl1- is bonded in a distorted T-shaped geometry to three equivalent Co2+ atoms.
CoCl2 is trigonal omega structured and crystallizes in the monoclinic C2/m space group. The structure is two-dimensional and consists of one CoCl2 sheet oriented in the (0, 0, 1) direction. Co2+ is bonded to six equivalent Cl1- atoms to form edge-sharing CoCl6 octahedra. There are two shorter (2.40 Å) and four longer (2.46 Å) Co–Cl bond lengths. Cl1- is bonded in a distorted T-shaped geometry to three equivalent Co2+ atoms.
CoCl2 is trigonal omega structured and crystallizes in the monoclinic C2/m space group. The structure is two-dimensional and consists of one CoCl2 sheet oriented in the (0, 0, 1) direction. Co2+ is bonded to six equivalent Cl1- atoms to form edge-sharing CoCl6 octahedra. There are two shorter (2.42 Å) and four longer (2.44 Å) Co–Cl bond lengths. Cl1- is bonded in a distorted T-shaped geometry to three equivalent Co2+ atoms.
CoCl2 is trigonal omega-like structured and crystallizes in the trigonal P-3m1 space group. The structure is two-dimensional and consists of one CoCl2 sheet oriented in the (0, 0, 1) direction. Co2+ is bonded to six equivalent Cl1- atoms to form edge-sharing CoCl6 octahedra. All Co–Cl bond lengths are 2.44 Å. Cl1- is bonded in a distorted T-shaped geometry to three equivalent Co2+ atoms.
A heat-driven catch-and-release strategy for CoCl 2 capture is described. It is based on the use of an immobilized neutral dicyclohexylacetamide-based receptor L supported on polystyrene (PS-L). An X-ray diffraction analysis of a single crystal of L·CoCl 2 revealed an ion-pair complex comprising a hexacoordinated cobalt cation [L·Co] 2+ and a tetrachlorocobaltate anion [CoCl 4 ] 2– . Temperature dependent binding was seen, as inferred from UV–vis spectroscopic studies. Fits to the van’t Hoff equation yielded values of ΔH° = 12.4 kJ/mol and ΔS° = 56.0 J/K·mol for L + CoCl2, and ΔH° = 16.5 kJ/mol and ΔS° = 85.0 J/K·mol for PS-L + CoCl 2 in 95% ethanol. Consequently, cobalt capture and release are mediated by heating and cooling, respectively. The material PS-L exhibits a preference for binding cobalt over manganese and nickel as inferred from Langmuir–Freundlich isotherm analyses that revealed binding constants of KLF = 88.5 M –1 for CoCl 2 , 52.7 M –1 for MnCl 2 , and 49.7 M –1 for NiCl 2 . In a simulated ion mixture containing equimolar CoCl 2 , MnCl 2 , and NiCl 2 , ICP-MS analyses served to confirm that cobalt was selectively enriched to 52 mol % (from an initial level of ca. 32 mol %) after one catch-and-release cycle and 76.6% after three cycles. Our experimental results were validated by density functional theory calculations, which also show stronger binding of Co over Mn and Ni to L.
COCl2 crystallizes in the tetragonal I4_1/a space group. The structure is zero-dimensional and consists of sixteen phosgene molecules. C4+ is bonded in a trigonal planar geometry to one O2- and two Cl1- atoms. The C–O bond length is 1.20 Å. There is one shorter (1.73 Å) and one longer (1.75 Å) C–Cl bond length. O2- is bonded in a single-bond geometry to one C4+ atom. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one C4+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one C4+ atom.
(CoCl2)2(N2)5(NO2)2 crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of twenty ammonia molecules; four cobaltchloride molecules; and four hydroxylamine, n-hydroxy- molecules.