Cyclohexylamine) 2 M(CN) 4 ⋅2C 6 H 6 (M = Cd or Hg)

Two new title compounds have been prepared in powder form. Their spectral data are found to be consistent with the structure foundin Hofmann-T_d-type clathrates.     

An Infrared and Raman Spectroscopic Study of pn-Td-Type dl% -Propylenediaminemetal(II) Tetracyanometallate(II) Benzene Clathrates: M(dl-pn)M'(CN)4.nC6H6 (M = Mn, M' = Zn, Cd or Hg; M = Cd, M' = Cd or Hg; 1≤n≤1.5)

IR spectra of Mn(dl-propylenediamine)M(CN)4.nC6H6 (M = Zn, n = 1.25; M = Cd, n = 1.00 or M = Hg, n = 1.18), and IR and Raman spectra of Cd(dl-propylenediamine)M(CN) 4. 1.5C6H6 (M = Cd or Hg) are reported. The spectral data suggest that the former three compounds are similar in structure to the latter two pn-Td-type clathrates.     

An Infrared Spectroscopic Study of Pyrazine- and 4,4′-bipyridyl-Td-type Clathrates: Mn (pyrazine) M(CN)4 benzene (M = Cd or Hg) and Mn (4,4′-bipyridyl) M(CN)4. benzene (M = Zn, Cd or Hg)

The infrared spectra of the title compounds have been reported. The spectral data suggest that the host framework of these compounds are similar to those of the en-T_d-type clathrate compounds. There is good evidence for hydrogen bonding from ligand molecules to benzene molecules as a to hydrogen bond.     

Vibrational Spectroscopic Investigations of M(Imidazole)2Ni(CN)4·2 Dioxane Clathrates

Four new clathrates of the formula M(Im)2Ni(CN)4·2·Dioxane (where M = Co, Ni, Cu, Cd; Im = Imidazole) have been prepared in powder form and their FT-IR and laser-Raman spectra are reported for the first time. These clathrates are analogues to the previously reported classical Hofmann type clathrates except for the copper clathrate. The Cu clathrate has different spectral features in comparison with its analogues due to the Jahn-Teller effect.     

Infrared Spectroscopic Study of the Hofmann-daon-Type Clathrates : M(1,8-diaminooctane)Ni(CN)4⋅G (M=Co, Ni or Cd; G=Aromatic Guest Molecules)

Infrared spectra of M(1,8-diaminooctane)Ni(CN)4G (M= Co, Ni or Cd; G=benzene, chlorobenzene, toluene, p-xylene, naphthalene or biphenyl) compounds are reported. The 1,8-diaminooctane molecules in the host permit the inclusion of bulky guest molecules. The spectral features suggest that the compounds are similar in structure to the Hofmann-type clathrates.     

Vibrational spectroscopic study on some Hofmann-Td type clathrates: Ni(4-phenylpyridine)2M(CN)4·2G (M=Cd or Hg, G=1,4-dioxane)

New Hofmann-T(d) type clathrates in the form of Ni(4-Phpy)(2)M(CN)(4)·2G (where 4-Phpy=4-phenylpyridine, M=Cd or Hg and G=1,4-dioxane) have been prepared in powder form and their FT-IR and Raman spectra have been reported. The results suggest that these compounds are similar in structure to the Hofmann-T(d) type clathrates.     

An Infrared Spectroscopic Study on the Hofmann-diam-type 1,12-Diaminododecanemetal(II) Tetracyanonickelate(II)-aromatic Guest Clathrates: M(H2N(CH2)12NH2)Ni(CN)4ċG(M=Co, Ni or Cd; G = Benzene, Naphthalene, Anthracene, Phenanthrene or Biphenyl)

Three Hofmann-diaminododecane-type clathrates of the form M(1,12-diaminododecane) Ni(CN)₄G (M = Co, Ni or Cd; G = benzene, naphthalene, anthracene, phenanthrene or biphenyl) have been prepared in powder form. The 1,12-diaminododecane molecules in the host lattice permit the inclusion of bulky guest molecules. The spectral features suggest that these compounds are similar in structure to the other Hofmann-diam-type clathrates.     

An infrared and raman spectroscopic study of pyrazinecadmium (II) tetracyanometalate (II) Benzene (1/1) clathrates: Cd(C4H4N2)Cd(CN)4⁗C6H6 and Cd(C4H4N2)Hg(CN)4⁗C6H6

Two new benzene clathrates of the form Cd(Pyrazine)M(CN)₄C₆H₆, where M = Cd or Hg, have been prepared and their infrared and Raman spectra are reported.     

An Infrared Spectroscopic Study on the Hofmann-diam-type 1,9-Diaminononanemetal(II) Tetracyanonickelate(II)-Aromatic Guest Clathrates: M(H2N(CH2)9NH2)Ni(CN)4 ċG(M = Cd or Ni; G = Benzene, Naphthalene, Anthracene or Phenanthrene

IR spectra of M(1,9-Diaminononane)Ni(CN)₄G (M = Cd or Ni; G = benzene, naphthalene, anthracene or phenanthrene) are reported. The spectral data suggest that the host structures in these clathrates are similar to those of Hofmann-, -diaminoalkane type clathrates.     

An infrared and Raman spectroscopic study of Td-type 4,4′-bipyridylcadmium(II) tetracyanometallate (II) benzene (1/2) clathrates: Cd(C10H8N2)Cd(CN)4 · 2C6H6 and Cd(C10H8N2)Hg(CN)4 · 2C6H6

Two new benzene clathrates of the form Cd(4,4-bipyridyl)M(CN)₄ · 2C₆H₆, (M=Cd or Hg) have been prepared in powder form. Their spectral data were compared with those of the corresponding host complexes and found to be consistent with the host structure found in Td-type clathrates.     

Vibrational spectroscopic study on some Hofmann type clathrates: M(2-(1-cyclohexenyl)ethylamine)2Ni(CN)4·2benzene (M=Ni and Cd)

New Hofmann type benzene clathrates in the form of M(CyHEA)2Ni(CN)4·2benzene (where CyHEA=2-(1-cyclohexenyl)ethylamine and M=Ni or Cd) have been prepared in powder form and FT-IR and Raman spectra have been reported. The results suggest that title compounds are similar in structure to Hofmann type clathrates and their structures consist of polymeric layers of |M-Ni(CN)4|∞ with the CyHEA molecule bounded to the metal atoms (M).     

Electrophilic Substitution Mn(II) → M(II) (M = Co,Ni, Cu,Zn, Cd) in Gelatin-Immobilized Mn2[Fe(CN)6]

Reactions of electrophilic substitution Mn(II) M(II) (M = Co, Ni, Cu, Zn, Cd) are studied in gelatin-immobilized Mn(II) hexacyanoferrate(II) systems brought in contact with aqueous solutions of metal chlorides MCl₂. As the result of this contact, Mn(II) is replaced by Co(II), Ni(II), Cu(II), Zn(II), or Cd(II) to give heteronuclear metal hexacyanoferrates(II) (MHCF) of Mn(II) and two-charged ions. Neither of the systems under study showed a complete substitution of Mn(II) or the formation of the respective mononuclear hexacyanoferrate(II) M₂[Fe(CN)₆]. When any of the above gelatin-immobilized MHCF was brought in contact with an aqueous solution of MnCl₂, no electrophilic substitution M(II) Mn(II) was observed even for a long contact time.     

Infrared spectroscopic studies of some piperidine metal(II) clathrates: M(C5H11N)2Ni(CN)4·G (M = Co,Ni; G = m-xylene,p-xylene or o-xylene; M = Ni; G = dioxane)

IR spectra of M(C₅H₁₁N)₂Ni(CN)₄·G (M=Co, Ni; G=o-, m- or p-xylene; M=Ni; G=dioxane) are reported. These clathrates are analogues to the previously reported classical Hofmann-type clathrates.     

Vibrational spectroscopic studies of some dimethylpyrazine cadmium (II) tetracyanonickelate benzene clathrates: [Cd(C6H8N2)Ni(CN)4]·C6H6

Two new cadmium dimethylpyrazine (2,3-dimethylpyrazine or 2,5-dimethylpyrazine) tetracyanonickelate benzene clathrates, [Cd(C₆H₈N₂)Ni(CN)₄]·C₆H₆, have been prepared in powder form and characterized by FT-IR spectroscopy, Raman spectroscopy, X-ray diffraction, thermal analyses and elemental analyses. Vibrational assignments are proposed for the bands of the host lattice and guest molecule. It is shown that the spectra are consistent with a proposed crystal structure for these compounds derived from X-ray diffraction measurements. The C, H, N, Cd and Ni analyses were carried out for all the compounds. Thermal behaviors of these compounds are followed using TG and DTA techniques. The FT-IR, Raman spectroscopic, XRD, thermal and elemental analyses results propose that these compounds are similar in structure to the Hofmann-type clathrates. Their structure consists of planar polymeric layers, {M–Ni(CN)₄}_∞, formed from Ni(CN)₄ anions coordinated to the bridging 2,3- or 2,5-dimethylpyrazine molecules bound directly to the cadmium. The cadmium atoms are bound to four N atoms of the CN ions and, the Ni atoms are surrounded by four C atoms of the CN groups in a square-planar layer.     

Synthesis, Spectroscopic, Thermal, and Structural Characterization of Complex Ferrocyanides KLnFe(II)(CN)6 ⋅ 3.5H2O (Ln = Gd-Ho)

Four new mixed metal cyanides of lanthanides (Ln = Gd-Ho) and iron with the general formula KLnFe(CN)₆ 3.5H₂O have been synthesized and characterized by chemical, infrared and thermal techniques. X-ray diffraction (XRD) analysis have shown that all the complexes have orthorhombic unit cells with space group Cmcm. Cyanide bridges link to nine coordinated LnN₆(H₂O)₃ groups to the octahedral FeC₆ groups. Cavities within the structure are occupied by uncoordinated zeolitic water molecules and potassium ions. The potassium cations form a pseudo-hexagonal 2D sublattice. Thermal decomposition involves two consecutive steps: dehydration and inorganic residue evolution to ternary oxides.     

Synthesis, structures, and properties of molybdenum and tungsten chalcogenide cubane complexes (NH4)6[M4Q4(CN)12]·6H2O (M=Mo or W; Q=S or Se)

Four new chalcogenide molybdenum and tungsten cubane clusters (NH₄)₆[M₄Q₄(CN)₁₂]·6H₂O (M=Mo or W; Q=S or Se) were prepared by high-temperature reactions of the triangular M₃O₇Br₄ complexes with KCN at 430 °C followed by crystallization from aqueous solutions of ammonium acetate. The molecular and crystal structures of (NH₄)₆[Mo₄S₄(CN)₁₂]·6H₂O, (NH₄)₆[W₄S₄(CN)₁₂]·6H₂O, and (NH₄)₆[W₄Se₄(CN)₁₂]·6H₂O were established by X-ray diffraction analysis. The mixed-valence cubane clusters are diamagnetic and isostructural and have the symmetryT _d . The clusters were characterized by IR and electronic spectroscopy. The data of cyclic voltammetry demonstrated that the [M₄Q₄(CN)₁₂] ⁿ⁻ clusters exist in three oxidation states from the most oxidized (n=6; 10 cluster electrons) to the most reduced electron-precise 12-electron species (n=8). Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 18–24, January, 2000.     

Theoretical Studies on the Thermo- electric Properties of Tin-based Clathrates： Cs8M4Sn42 （M = Zn,C小 Hg） and Cs8Sn44□2

The site occupancies and thermoelectric properties of tin-based clathrates Cs8M4Sn44□2 （M = Zn, Cd, Hg） and CssSn44□2 were studied by the first principle calculations. We had provided an efficient way to probe the relationship between the crystalline structure and power factor. Detailed analyses indicated the p states of Sn at 16i and 24k sites together with the p states of M substitute contributed significantly to the maximum power factor, yet Cs atoms nearly did not. The dangling bonds of vacancies in Cs8Snn44□2 are also discussed. The power factors of p- and n-type CssMaSn42 and Cs8Sn44□2 at optimal temperature and carder concentration are predicted. Our results suggest that Cs8ZnaSn44□2 is a promising candidate at the 5.25 ×10^19 cm-3 hole carrier concentration as a high temperature thermoelectric material that is competitive to the state-of-art Ge-based clathrate thermoelectric materials.     

Crystal structure of CsLnFe(CN)6·5H2O (Ln=Ce,Pr, Nd), CsCeFe(CN)6·4H2O,and TlTmRu(CN)6·3H2O

We have investigated the crystal structures of CsLnFe(CN)₆·nH₂O (Ln=lanthanide, n=4,5), as well as TlTmRu(CN)₆·3H₂O. These phases can be thought of as derivatives of LnFe(CN)₆·4H₂O, where, simultaneously, an alkali ion (or Tl⁺) is introduced while the valence of Fe is reduced from Fe³⁺ to Fe²⁺. A new arrangement of the structural units is observed in the CsLnFe(CN)₆·5H₂O, where the coordination of the Ln-ion is changed to a bisdisphenoid. The resulting LnN₅O₃ units alternate with Fe(CN)₆ units to form an overall rocksalt-type ralted lattice that accommodates the alkali ions in interstitial sites. Due to the arrangement of the water molecules, a layer structure results.     

Syntheses and crystal structures of two Cd(II) coordination polymers: one-dimensional chain [Cd(C4H6N2)2(C4H2O4)(H2O)2] n and two-dimensional sheet [Cd(C4H6N2)(H2O)(C4H4O4)] n · n H2O

Two new Cd(II) coordination polymers, [Cd(C₄H₆N₂)₂(C₄H₂O₄)(H₂O)₂] _n (1) (where C₄H₆N₂?=?2-methylimidazole, C₄H₂O₄?=?fumarate), and [Cd(C₄H₆N₂)(H₂O)(C₄H₄O₄)] _n ?·?nH₂O (2), (where C₄H₄O₄?=?succinates), have been prepared and structurally characterized by single crystal X-ray diffraction. Complex 1 crystallizes in the triclinic space group P 1 in a one-dimensional chain structure, in which carboxy is monodentate; a three-dimensional supermolecular network structure was formed through hydrogen bonding. In complex 2, the coordination geometry of the Cd atoms is a pentagonal bipyramid, and a two-dimensional sheet is formed though carboxyl group bridging. In 1 and 2, IR spectra indicate the presence of bridging carboxyl groups, confirmed by structure analyses.     

[M(μ-O2C-C6H4-CO2)(NH3)2] (M = Cu,Cd; O2C-C6H4-CO2 = benzene-1, 4-dicarboxylate,terephthalate): 1D Coordination Polymers with Strong Inter-Chain Hydrogen Bonding

Compounds [M(μ-O₂C-C₆H₄-CO₂)(NH₃)₂] crystallize as straight- (M = Cu) and kinked-chain (M = Cd) coordination polymers through the bridging action of the bis-mono (Cu) and bis-bidentate (Cd) benzene-1, 4-dicarboxylate (terephthalate) ligand. N-H···O hydrogen bonding connects the chains to a three-dimensional supramolecular network. Thermogravimetry shows the compounds to be stable up to 255 °C (M = Cu) and 70 °C (M = Cd) where decomposition starts with the loss of one ammin ligand. [Cd(μ-O₂C-C₆H₄-CO₂)(NH₃)₂] exhibits a luminescence with λ_{em, max} = 392 nm (λ_ex = 240 nm) on the same order of magnitude as Na₂(O₂C-C₆H₄-CO₂).