Inorganic Chemistry Communications (v.6, #4)

Contents List (iii-iv).

▪ (R=alkyl or aryl) complexes as catalysts for ethylene polymerization by M.F.N.N Carvalho; K Mach; A.R Dias; J.F Mano; M.M Marques; A.M Soares; A.J.L Pombeiro (331-334).
▪ (R=alkyl or aryl) complexes in combination with methylaluminoxane were found to be highly efficient catalysts towards ethylene polymerization. The species with aromatic R groups display higher activity than those with aliphatic ones. This tendency could not be correlated with the electronic properties of the complexes that were evaluated by cyclic voltammetry. The polyethylenes obtained in the catalytic processes were characterized by 1H NMR and DSC.
Keywords: Catalysis; Polymerization; Ethylene; Titanium complexes; Electrochemistry;

Chemical speciation and biodistribution studies of copper(II) complexes of poly(amine)amide ligands by Edmund T Nomkoko; Graham E Jackson; Bandile S Nakani (335-338).
Formation constants of Cu2+, Zn2+ and Ca2+ with 3,3,9,9-tetramethyl-4,8-diazaundecane-2,10-dione dioxime (L1), N,N -bis(2-hydroxyiminopropionyl)propane-1,3-diamine (L2) and (1,15)-bis(N,N-dimethyl)-5,11-dioxo-8-(N-benzyl)-1,4,8,12,15-pentaazapentadecane (L3) were determined by glass electrode potentiometry at 25 °C and an ionic strength of 0.15  mol dm −3 . Zinc and calcium were found to form weak complexes with all three ligands. Copper formed stable complexes with the [CuLH−1] species predominating. Electronic spectra suggest that [CuLH−1] is square-planar. Speciation calculations using a blood-plasma model predict that L1 and L2 are able to mobilise Cu2+ in vivo. Biodistribution studies using 64Cu-labeled [CuLH−1] show a high uptake of copper by the liver.
Keywords: Formation constants; Potentiometry; Speciation; Biodistribution; Copper(II); Poly(amine)amide ligands;

In this paper we present, for the first time, the NMR investigation of the solution structure of the alkyl cationic titanium compound produced by reaction of 1,3-dimethoxy-p-But-calix[4]arene titanium dichloride and methylaluminoxane in the required conditions of ethylene polymerization. The role the methylalumoxane plays in the reaction with titanium compound is analyzed by NMR.
Keywords: Calixarene; Titanium cation; Polyethylene; Methylalumoxane;

The stoichiometric reaction of Cu2CO3(OH)2, iminodiacetic acid [H2IDA=HN(CH2CO2H)2)] and 2,4-bipyridine (2,4-bipy) in water yields crystalline samples of {[Cu(IDA)(2,4-bipy)]·H2O} n . The compound was studied by thermal, spectral (FT-IR and reflectance), magnetic (ESR and susceptibility) and X-ray diffraction methods. The structure was solved and refined to a final R 1=0.035. The Cu(II) atom exhibits a type 4 + 1 coordination and 2,4-bipy ligand links the metal by its N4-donor. IDA exhibits a mer-tridentate chelating role and uses a syn-anti-bridging carboxylato group to give polymeric chains extending parallel to the c axis, leaving all 2,4-bipy ligands towards the same side. Water molecule reinforces the chain stability forming H-bonds with two O(carboxyl) acceptors from adjacent complex units. Both pyridyl rings of 2,4-bipy are nearly coplanar (1.0(2)°). Adjacent 2,4-bipy ligands of the same complex chain define an open dihedral angle (69°). 2,4-bipy ligands belonging to symmetry related chains stack both pyridyl rings at 3.40 Å, thus forming a 2D framework with IDA ligands lying towards both external faces and N-heterocyclic ligands inside. In the crystal N(IDA)-H⋯O(IDA) hydrogen bonds connect up and down adjacent 2D frameworks in a 3D network. Poly-{(N4-2,4-bipyridine)-μ-(N,O,O ,O ′′-iminodiacetato)copper(II) hydrate} builds a 2D framework of complex chains which leaves the Cu(IDA) moieties towards both external surfaces and stacks anti-parallel pairs of 2,4-bipy ligands inside involving its two pyridyl rings. Bi-layered 2D frameworks are connected by N–H⋯O bridges in the 3D crystal network.
Keywords: Copper(II) complex; Crystal structure; Bipyridine; Iminodiacetato;

Highly proton-conductive copper coordination polymer, H2 dtoaCu (H2 dtoa=dithiooxamide anion) by Hiroshi Kitagawa; Yuki Nagao; Musashi Fujishima; Ryuichi Ikeda; Seiichi Kanda (346-348).
Room-temperature proton conductivity, coordination geometry, and pore-diameter distribution of the title Cu(II) coordination polymer have been investigated by AC conductivity, EXAFS, and N2 adsorption isotherm measurements. The AC proton conductivity (σ p) obtained from Cole–Cole plot analysis under relative humidity of 75% and 300 K exhibits a considerable high value of 10−6   S cm −1 as a room-temperature σ p. The mechanism of proton conduction seems to be similar to that of a proton-exchange membrane, Nafion, which contains much cluster of water molecules in the porous space of the polymer. The present Cu coordination polymer was revealed to possess porous space of about 6 Å, which includes much water molecules more than 10H2O per unit cell. The dimeric Cu(II) square-planar coordination geometry was confirmed by EXAFS analysis using synchrotron radiation source at SPring-8.
Keywords: Solid state ionics; Proton conduction; Hydrogen storage; Proton-exchange membrane;

Preparation of GaP/RhB nanocomposite by ultrasonic irradiation by Guixia Shi; Zhengang Liu; Xiaopeng Hao; Deliang Cui; Yujun Bai; Qilong Wang (349-351).
The GaP/rhodamine B (RhB) nanocomposite was synthesized by ultrasonic irradiation method and characterized by transmission electron microscope, Fourier transformation infrared spectroscopy and Raman spectroscopy. The results show that the morphology of GaP/RhB nanocomposite changed from “superlattice” to asymmetric core-shell and finally to symmetric core-shell microstructure with the extending of irradiation time. The possible reason for the changing of morphology of GaP/RhB nanocomposite was investigated.
Keywords: Ultrasonic irradiation; GaP/RhB nanocomposite; Morphology;

Fully methylated η34-allyldiene(η5-cyclopentadienyl)titanium(II) (1) reacts with alkynylketones RCCC(O)Me (R=SiMe3 (3a) and ferrocenyl (3b)) to give the expected products of the CO group insertion into one Ti–CH2 bond 4a and 4b, respectively. Compound 4a could not be isolated in pure form due to its high solubility; a minor product of two-fold addition (5) was isolated instead. Complex 5, formally [ 1 +2  3a ], was characterized as a monocyclopentadienyl bis(alkoxy)organyl complex, where the alkoxyorganyl ligand arises from CO insertion into one Ti–CH2 and the Ti–C(cyclopentadienyl) bonds. The structures of compounds 4b and 5 were determined by single-crystal X-ray diffraction.
Keywords: Titanium; Cyclopentadienyl; Ferrocene; Alkyne; Ketone; X-ray crystallography;

By the reaction of the tetradentate Schiff base ligand H2salbn, N,N -disalicylidene-1,4-diaminobutane with FeIIICl3·6H2O in the presence of Et3N in MeOH a dinuclear iron(III) complex, [FeIII(salbn)(μ-OMe)]2 (1), has been obtained, whereas in EtOH, dinuclear complexes, [FeIII(μ-salbn)]2(μ-O) (2) and [FeIII(salbn)]2(μ-salbn) (3), are obtained. The structure of the complex 1 consists of two Fe(III) centers with one tetradentate salbn ligand (N2O2) which are bridged by two methoxo groups to yield a planar Fe2O2 core. On the other hand, in the complex 2, each of the two Fe(III) ions has a five-coordinate structure in which both salbn ligands act as a bridging didentate ligand and one oxygen atom bridges two Fe(III) ions to form a μ-oxo structure. The structure of the complex 3, which was obtained by accompanying with complex 2, consists of two six-coordinate Fe(III) centers in which each Fe(III) ion is coordinated by a tetradentate salbn ligand (N2O2) and one bridging salbn ligand (NO).
Keywords: Iron(III) complex; Dinuclear structures; Tetradentate Schiff base ligand; Molecular structure; μ-Oxo structure;

A dinuclear copper(I) complex [Cu2(μ-dppb)2(CH3CN)4](BF4)2 (dppb=1,4-bis(diphenylphosphino)benzene) has been prepared and characterized by X-ray crystallography, absorption and luminescence spectrometry. The two copper atoms are double linked by two dppb ligands to form a metallophane with the two bridging phenyl rings parallel to each other. The core cyclophane-like structure adopts a chair conformation constructed by four coplanar P atoms and two phenyl rings from two dppb ligands, and the two copper atoms located above and below the mean plane. At room temperature, the complex in solid state exhibits photoluminescence originated from the intraligand excited state perturbed by copper coordination. The title complex may serve as a pre-organized dimetal building block for constructing novel supramolecular system.
Keywords: Copper(I) metallophane; Crystal structure; 1,4-Bis(diphenylphosphino)benzene; Photoluminescence;

The first two examples of diamineruthenium(II) complexes containing the hemilabile methoxyethyldimethylphosphine ligand, Cl2Ru(en)(η1-Me2PCH2CH2OMe)2 (2a) and Cl2Ru[(R,R)-dpen](η1-Me2PCH2CH2OMe)2 (2b) (en=1,2-diaminoethane, (R,R)-dpen=1R,2R-1,2-diamino-1,2-diphenylethane) have been synthesized and structurally characterized.
Keywords: Ruthenium(II) complexes; Ether-phosphines; Diamine ligands; Crystal structures;

Inorganic–organic hybrid material containing β-cage: {[H2(en)]Co2(ox)(V4O12)} n by Cheng-Ling Pan; Ji-Qing Xu; Kai-Xue Wang; Xiao-Bing Cui; Ling Ye; Zheng-Liang Lu; De-Qing Chu; Tie-Gang Wang (370-373).
By using an organic ligand, a new inorganic–organic hybrid compound of cobalt oxalate-vanadate, {[H2(en)]Co2(ox)(V4O12)} n 1, where en = ethylenediamine, ox = oxalic acid, has been synthesized hydrothermally from V2O5,CoCl2·6H2O,H2C2O4·2H2O and en. Crystal data 1, orthorhombic, Cmcm space group, a=11.624(2), b=9.968(2), c=14.900(3) Å, R1=0.0298, wR2=0.1172. Compound 1 possesses a three-dimensional open-framework with β-cage and is an antiferromagnetic matter.
Keywords: Hybrid material; Cage; Cobalt oxalate-vanadate; Three-dimensional; Hydrothermal synthesis;

Novel dinuclear oxovanadium (IV) complexes having the formula [(VO)2(dpp)3(bpy)2]NO3·2H2O (1), [(VO)2(dpp)3(phen)2]-NO3·H2O (2), [(VO)2(bmp)3(bpy)2]NO3·H2O (3), and [(VO)2(bmp)3(phen)2]NO3·H2O (4), and copper (II) complexes having the formula [Cu2(bmp)2(phen)2](NO3)2·MeOH·H2O (5), and [Cu2(bmp)2(bpy)2](NO3)2 (6) (where Hdpp=diphenylphosphinic acid, Hbmp=bis(4-methoxyphenyl)phosphinic acid, bpy=2,2-bipyridine, and phen=1,10-phenanthroline) with (μ-phosphinato)-bridges, 16, have been prepared and characterized. Crystal structure of complex 2 reveals that two vanadium ions are linked by tris(μ-phosphinato)-bridges. The magnetic susceptibility data for 13, and 6 conform to the usual dimer equation with −2J values of 16–24 cm−1, indicating a weak antiferromagnetic interaction between vanadium(IV) ions.The oxidation of cinnamyl alcohol was studied using complexes 16 as catalyst and molecular oxygen as an oxidant. In the presence of complex 3 as a catalyst, cinnamyl alcohol was oxidized to cinnamaldehyde 61% yield in 7 h. Consequently, complex 3 activates oxygen, and then alcohol was quite efficiently oxidized by activated oxygen.Novel dinuclear oxovanadium (IV) complexes having the formula [(VO)2(dpp)3-(bpy)2]NO3·2H2O (1), [(VO)2(dpp)3(phen)2]NO3·H2O (2), [(VO)2(bmp)3(bpy)2]NO3·H2O (3), and [(VO)2(bmp)3(phen)2]NO3·H2O (4), and copper (II) complexes having the formula [Cu2(bmp)2(phen)2](NO3)2·MeOH·H2O (5), and [Cu2(bmp)2(bpy)2](NO3)2 (6) (where Hdpp=diphenylphosphinic acid, Hbmp=bis(4-methoxyphenyl)phosphinic acid, bpy=2,2-bipyridine, and phen=1,10-phenanthroline) with (μ-phosphinato) bridges, 16, have been prepared and characterized. The oxidation of cinnamyl alcohol using complexes to molecular oxygen as an oxidant. In the presence of complex 3 as a catalyst, cinnamyl alcohol was oxidized to cinnamaldehyde 61% yield in 7 h.
Keywords: Dinuclear oxovanadium(IV) complex; Dinuclear copper(II) complex; Phosphinato bridge; Antiferromagnetic; Reactivity; Oxidation;

Syntheses, structures and magnetic properties of multinuculear manganese complexes with Schiff base ligands by Norihisa Hoshino; Tasuku Ito; Masayuki Nihei; Hiroki Oshio (377-380).
Multinulear manganese complexes with Schiff base ligands, [{MnIII 43-O)(sae)4(μ-N3)(CH3OH)}2(μ-N3)]N3 ([1]N3), [MnIII 63-O)2(sae)6(NCS)2] (2) and [MnII 4MnIII 2(sae)6(CH3OH)2Cl2] (3) (H2sae=2-salicylideneaminoethanol), were prepared and the crystal structures and magnetic properties were studied.
Keywords: Magnetic properties; Manganese complex; Schiff base; Crystal structure;

Two nickel(II) complexes having the general formula [Ni(bhac)L] with tridentate ONO-donor acetylacetone benzoylhydrazone (H2bhac) and monodentate N-donor heterocycles (L=3,5-dimethylpyrazole (Hdmpz) and imidazole (Himdz)) are reported. The complexes were synthesized in ethanol media by reacting Ni(O2CCH3)2·4H2O, H2bhac and L in 1:1:1 mole ratio and characterized by analytical, magnetic and spectroscopic methods. X-ray crystal structures of both complexes have been determined. In each complex, the metal ion is in square-planar N2O2 coordination geometry. In the solid state, a one-dimensional assembly of the [Ni(bhac)(Himdz)] molecules is formed via intermolecular hydrogen bonds between the imidazole N–H groups and the uncoordinated N-atoms of the deprotonated amide functionalities. On the other hand, two [Ni(bhac)(Hdmpz)] molecules are involved in a pair of complementary hydrogen bonds between the pyrazole N–H groups and the coordinated O-atoms of the deprotonated amide functionalities forming a dinuclear species.
Keywords: Nickel(II) complexes; Mixed-ligand; Square-planar; Crystal structures; Hydrogen bonding; Self-assembly;

A mononuclear tin(IV) complex {α-[Sn(edt)2(tdet)]}·{β-[Sn(edt)2(tdet)]} was synthesized by the reaction of Sn(edt)2 and NaOH under hydrothermal conditions and characterized by X-ray structure analysis. Under hydrothermal conditions, two edt ligands turned into one tdet and this provides a new strategy for the preparation of H2 tdet from cheap material. In the complex, the distances of Sn–S (thiolate) are about 2.4 Å, but the distances of Sn–S (thioether) are about 2.8 Å. Two isomers were found in the molecule.A new strategy for the preparation of 2,2-thiodienthanethiol from cheap material was proposed.
Keywords: 2,2-Thiodienthanethiol; Tin(IV); Isomer; Hydrothermal condition;

Crystal structure and photo-induced property of two-dimensional silver(I) complex with 1,3,5-tris(benzylsulfanyl)benzene by Yusaku Suenaga; Hisashi Konaka; Takeshi Sugimoto; Takayoshi Kuroda-Sowa; Masahiko Maekawa; Megumu Munakata (389-393).
The silver(I) complex [Ag2(3bsb)2(ClO4)2] (1) (3bsb; 1,3,5-tris(benzylsulfanyl)benzene) has been prepared and its molecular structure was determined by X-ray crystallography. In 1, the silver ion prefers a tetrahedral coordination geometry and produces a two-dimensional sheet structure containing dimeric units. Irradiation of this complex 1 with light changes its color from white to pink; heat or exposure to acetone vapor makes the irradiated sample revert back to white. However, only 3bsb has no characteristic like this photochromism.
Keywords: Silver(I) coordination polymer; 1,3,5-tris(benzylsulfanyl)benzene; Two-dimensional sheet structure; Photochromism;

A novel paddle-wheel shaped spirocyclic cyclotetraphosphazene from the thermolysis of a P(III) azide by Praveen Kommana; Sudha Kumaraswamy; K.C.Kumara Swamy (394-397).
The spirocyclic cyclotetraphosphazene [CH2(6-t-Bu-4-Me-C6H2O)2PN]4 (2) is obtained as one of the products from the thermolysis of the azide CH2(6-t-Bu-4-Me-C6H2O)2PN3 (1). An X-ray structure determination reveals that the compound has a paddle-wheel shaped structure with the phosphorus bearing only eight-membered rings [phosphazene/phosphocin]. The eight-membered phosphocin ring in 2 has a tub conformation, in contrast to the boat–chair conformation present in 1, possibly due to weak C–H…N interactions. Compound 2 could not be prepared from the traditional route of starting from octachlorocyclotetraphosphazene [N4P4Cl8] and hence the azide route is the only accessible pathway for 2.Compound 2 is the first example of an all-spirocyclotetraphosphazene accessible by the thermolysis of the P(III) azide 1, but not from the traditional route of replacement reaction from N4P4Cl8.
Keywords: Cyclophosphazene; Spirocyclic; Azide; X-ray structure;

Zinc complex of N-confused calix[4]phyrin by Hiroyuki Furuta; Tomoya Ishizuka; Atsuhiro Osuka (398-401).
A zinc(II) complex of N-confused calix[4]phyrin (isoporphyrin) (2-Zn) has been synthesized and the structure was revealed by 1 H NMR and X-ray analyses. The atomic distance between zinc metal and the inner-core carbon was about 0.2 Å longer compared with that of zinc(II) N-confused porphyrin complexes, suggesting the weaker side-on η 1-coordination with the inner-core-carbon in 2-Zn.
Keywords: N-confused porphyrin; Isoporphyrin; Zinc complex; Organometallics; Side-on η 1-coordination;

Triethylammonium benzene-1,3,5-tricarboxylato(pyridine)zinc(II): a two-dimensional undulating mesh network by Gang Wu; Xin Shi; Qianrong Fang; Ge Tian; Lifeng Wang; Guangshan Zhu; Anthony W. Addison; Yen Wei; Shilun Qiu (402-404).
A two-dimensional layered metal-organic framework material (HN(CH2CH3)3)Zn(BTC)(Pyd) with chiral trigonal pores has been prepared with HTEA+ as the structure-directing agent under mild synthetic condition. Crystal data for (HTEA)Zn(BTC)(Pyd): M=450.77, Orthorhombic, space group Pbca, a=13.652(4) Å, b=16.345(4) Å, c=18.734(6) Å, V=4180(2)  A ̊ 3 , T=293 K, Z=8, μ=1.213  mm −1 , D c =1.439  mg/m 3 . 9197 reflections measured, 2972 observed (R int=0.0905), which were used in all calculations. The final R 1=0.0498, R ω =0.1134. The structure was solved by direct methods using SHEUXTU-97.
Keywords: Coordination polymer; Template; BTC; Chiral;

Synthesis and X-ray structure of octanuclear copper cluster Cu8(μ-I)(μ6-S)(DTP)6 by Yu-Biao Chen; Zhao-Ji Li; Ye-Yan Qin; Yao Kang; Jian-Kai Cheng; Rui-Feng Hu; Yi-Hang Wen; Yuan-Gen Yao (405-407).
The title compound, Cu8(μ-I)(μ6-S)(DTP)6 (DTP=diethyldithiophosphate), has been synthesized by the reaction of Mo33-S)(μ-O)(μ-S)2(DTP)4(CH3CN) with CuI, and its structure has been determined by X-ray crystallography. Crystal data: C24H60Cu8IO12P6S13, Mr=1778.54, trigonal, R-3, Z=3, a=20.734(3), c=11.874(2) Å, V=4420.7(13)  A ̊ 3 , D c =2.004  g cm −3 . An interstitial μ6-S is established in the Cu8 cubic center. The octanuclear cubes are linked together by μ-I so that a strict infinite linear polymeric cluster chain is formed along the [0 0 1] direction.
Keywords: Crystal structures; Copper complexes; Cluster complexes; Octanuclear complexes;

The synthesis and crystal structure of [M{H2B(tz*)2}2(H2O)] (M=Cu, Zn and tz*=3,5-dimethyl-1,2,4-triazole) by Wei-Zheng Shen; Feng Kang; Ying-Ji Sun; Peng Cheng; Shi-Ping Yan; Dai-Zheng Liao; Zong-Hui Jiang (408-411).
New ligand [KH2B(tz*)2] (tz*=3,5-dimethyl-1,2,4-triazolyl) has been synthesized and the reactions of two different metal salts (copper and zinc) with the new ligand in agar gave two similar crystalline polymorphic forms: [Cu{H2B(tz*)2}2(H2O)] (1) and [Zn{H2B(tz*)2}2(H2O)] (2). A single crystal X-ray study revealed that the compound 1 was the monoclinic system with space group C2/c and a=8.462(3) Å, b=14.039(6) Å, c=19.991(8) Å, β=94.622(7)°, Z=4, R 1=0.0451, wR 2=0.1110. And the compound 2 was the monoclinic system with space group C2/c and a=8.4214(4) Å, b=13.8765(7) Å, c=20.2969(6) Å, β=95.615(2)°, Z=4, R 1=0.0667, wR 2=0.1375. The metal(II) ion in the complex is five-coordinated with four nitrogen atoms which come from triazolyl and one oxygen atom which come from water molecular. In both compounds, the hydrogen atoms of water molecule are connected by hydrogen bonding with N atoms of two adjacent complex molecules to form 2-D planes. The spectroscopic results are consistent with the crystallographic study.
Keywords: Copper(II) complexes; Zinc(II) complexes; Crystal structure; Hydrogen bonding; Triazole;

Self-assembly of one-dimensional coordination polymer from nickel(II) macrocyclic complex and 2,6-pyridinedicarboxylate ligand by Ki-Young Choi; Haiil Ryu; Youn-Mook Lim; Nack-Do Sung; Ueon-Sang Shin; Mancheol Suh (412-415).
The reaction of [Ni(L)(H2O)2]Cl2 (L=2,5,9,12-tetramethyl-1,4,8,11-tetraazacyclotetradecane) with 2,6-pyridinedicarboxylate (pdc) generates one-dimensional coordination polymer [Ni(L)(pdc)]·H2O (1). In the polymeric framework, the nickel(II) ion has an octahedral geometry and is bridged by two pdc ligands. The magnetic susceptibility measurement for 1 exhibits a weak antiferromagnetic interaction (J=−1.04(3)  cm −1 ; H=−JΣS i ·S i+1) between the S=1 nickel(II) paramagnetic centers.
Keywords: Crystal structure; Nickel(II) complex; Antiferromagnetic interaction; One-dimensional polymer; 2,6-Pyridinedicarboxylate;

The complex salts [M(N-N)3][Cu(i-mnt)2] [M = Fe(II), Co(II), Ni(II) or Cd(II); N-N = 1,10-phenanthroline (phen) or ethylenediamine (en); i-mnt2− = isomaleonitriledithiolate] and heterometallic coordination polymers MCu(i-mnt)2 [M=2Ag(I), Cd(II), Hg(II) or Pb(II)] have been synthesized by stoichiometric reactions between K2[Cu(i-mnt)2] and [M(N-N)3]X2 or MX2 [X=Cl, NO3 or 1/2SO4 2−]. These have been characterized by elemental analyses, solution conductivity and magnetic susceptibility measurements, relevant spectroscopies (IR, UV–Visible and EPR) and solid phase conductivity techniques. Complete quenching of paramagnetism shows strong antiferromagnetically coupled Cu(II) ions in the bridged heterometallic complexes MCu(i-mnt)2 producing a polymeric array. The coordination polymers MCu(i-mnt)2 exhibit σ rt=10−9–10−6   S   cm −1 and show semiconductivity in the 313–393 K range while complex salts [M(N-N)3][Cu(i-mnt)2] are insulators at room temperature and at higher temperature as well. Iodine-doped products of complex bimetallic salts and coordination polymers are conducting at room temperature and exhibit semiconducting behaviour over above temperature range. Conductivities of the coordination polymers are significantly higher compared to the bimetallic salts.
Keywords: Heterobimetallic isomaleonitriledithio complexes; I2-Doped complexes; Semiconductor; IR spectra;

Condensation of coordinated acetonitrile and one of the amine ligands in [(NH3)4Co·μ(NH2,NO2)·Co(NH3)4](CF3SO3)4. H2O (2c) results in the formation of a bridging acetamidino group. It is assumed that an intramolecular reaction occurred in which a coordinated amido ligand attack the substituted acetonitrile group to yield the third bridge. In this process the amido and acetonitrile groups which are coordinated to adjacent cobalt centers should bear a syn relationship. Synthesis and characterization of [(NH3)3Co·μ(CH3C(NH)2,NH2,NO2)·Co(NH3)3](CF3SO3)3 (5) is reported here.
Keywords: Binuclear cobalt complex; Triple bridging; Intramolecular condensation; Acetamidino bridge;

Hyper-Rayleigh scattering of nanoscale CdS colloid and its formation process by Yu Zhang; Ming Ma; Xin Wang; Degang Fu; Haiqian Zhang; Ning Gu; Juzheng Liu; Zuhong Lu; Ling Xu; Kunji Chen (427-430).
Nanoscale CdS colloid has exhibited great second-order optical nonlinearities measured by hyper-Rayleigh scattering (HRS) technique. Here a further study on electrolyte concentration dependence of HRS signal of nanoscale CdS colloid is carried out in order to exclude the possible contributions of some third-order nonlinear optical processes based on colloidal particle surface electric field and solvent field. Results show that the HRS signal remains unchanged with increasing electrolyte concentration, implying that the HRS signal arises indeed from second-order polarization (including bulk-like polarization and surface polarization) of CdS nanoparticles rather than the third-order processes. Furthermore, HRS signal variation during the formation of CdS colloid is studied for the first time. An obvious enhancement of HRS signal intensity is observed immediately once Cd2+ and S2− ions are mixed. After that, HRS signal decreases toward a constant value with time. This is explained in terms of surface contribution due to large surface-to-volume atomic ratio for nanoparticles.
Keywords: CdS colloid; Formation process; Hyper-Rayleigh scattering; Surface contribution;