A novel dimeric complex of dysprosium with pyridine-3-carboxylic acid: structure and photophysical properties

A dimeric complex [Dy(NIC)₃(H₂O)₂]₂ (HNIC = pyridine-3-carboxylic acid) has been synthesized. X-ray analysis reveals that it forms a novel dimeric structure through bridged oxygen atoms of carboxylate groups. The title complex crystallizes in space group P2₁/c, with a = 9.560(3), b = 11.601(4), c = 17.731(5)?Å, β = 91.572(4)°, V = 1965.7(10)?ų, D _c = 1.909?Mg/m³, Z = 2, F(000) = 1100, GOF = 0.956, R ₁ = 0.0248. Photophysical properties have been studied with ultraviolet absorption, excitation and emission spectra. The complex exhibits strong blue emission.     

密度泛函理论研究MN@H_2O (M=Ga,Ge, In,Sn, Sb; N=M,Al)团簇的特性

采用密度泛函理论的B3LYP, B3P86, B1B95, P3PW91和PBE1PBE方法结合SDD, LANL2DZ和CEP-121G基组计算了d~(10)组态二聚物MN(M=Ga, Ge, In, Sn和Sb; N=M和Al)的几何结构.采用B3P86/SDD进一步研究了MN@H_2O团簇的几何结构及吸附能.结果表明,水分子结合在二聚物M_2上时,对二聚物影响较大,对水分子自身影响较小.将M_2中Ga, Ge, In, Sn或Sb替换一个原子为Al时,水分子在GeAl和SnAl上的吸附能变化较大,而在GaAl, InAl和SbAl上吸附能变化较小.另外, H_2O吸附在Ga, Ge, In, Sn和Sb上时,与吸附在Al上时,吸附能的变化不大.     

Radiation centre of institute of physical chemistry in Moscow

Radiation centre of the Institute of Physical Chemistry of Russian Academy of Sciences (Moscow) is described. It has four ⁶⁰Co γ-ray sources and four electron accelerators, three of them being linear ones. The brief consideration of researches and developments in radiation chemistry and radiation processing is conducted.     

Spirobicyclic diamines. Part 3: Synthesis and metal complexation of proline-derived [4.4]-spirodiamines

The syntheses of racemic and homochiral [4.4]-spirolactams, starting from l-proline, in good yields are described. Reduction of the lactam carbonyl group of spirolactams, containing chiral substituents on the lactam nitrogen, with lithium aluminium hydride, gives a series of homochiral [4.4]-spirodiamines. The crystal structure of one of these spirodiamines on complexation with zinc chloride was obtained. Interestingly it showed a hydrogen-bonded dimeric structure, where the monomers are diastereoisomeric diamines.     

Synthesis,Crystal Structure and Thermal Properties of a Novel Ferrocenecarboxylato-Bridged Zinc(II) Dimer [Zn2(µ-OOCFc)4(3-PyCOOCH3)2]

A novel ferrocenyl dimer [Zn₂(μ-OOCFc)₄(3-PyCOOCH₃)₂] (Fc=(η⁵-C₅H₅)Fe(η⁵-C₅H₄)), 1, was obtained by the reaction of Zn(OAc)₂·2H₂O with sodium ferrocenecarboxylate and 1,4-butanediol dinicotinate in methanol solution. X-ray structural analysis reveals that the compound contains two zinc(II) centers symmetrically bridged by four ferrocenecarboxylate anions as O,O′-bridging ligands, leading to a dimeric tetrabridged [Zn₂(μ-OOCFc)₄] core. The zinc(II) ion is in a distorted octahedral environment with four oxygen atoms from four distinct ferrocenecarboxylates, a nitrogen atom from the ligand NC₅H₄CO₂CH₃, and another zinc atom. The symmetry of the complex in the paddle-wheel structure brings the metal centers close, the Zn … Zn intradimer distance being 2.934(11) Å. It is the first example of a zinc(II) dimer with ferrocenecarboxylate anion ligands. Its thermal properties were measured in air.