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1.
cis-[Co(bipy)2(CN)2] complex was successfully prepared from the reaction of [Co(CN)2] with 2,2′-bipyridine in ethanol 96%. The product of complex synthesized was light brown crystal with percent yield of 75.86%.
The IR spectrum of this complex showed strong characteristics vibration band at 1471.9 and 1442.75 cm−1 for C=N stretching, 1664.57 cm−1 for C=C aromatic, 1600.9 cm−1 1 for HC=CH aromatic, 653.87 cm−1 for pyridine ring on 2,2′-bipyridine ligand, 3109.25 and 3080.32 cm−1 for C-H of aromatic ring. The thermogram of DTA-TG analysis showed 4 endothermic peaks at temperature of 53.4, 323.2, 444.2,
and 526.4°C, where the bond breaking of the complex occurred at different temperatures. The result of moment magnet measurement
of the complex showed that it was a high spin complex with moment magnet value of 3.68 BM, so it is a paramagnetic complex. 相似文献
2.
Sofia Nikolaou Daniela M. Tomazela Marcos N. Eberlin Henrique E. Toma 《Transition Metal Chemistry》2008,33(8):1059-1065
The polymetallic [Ru3O(CH3COO)6(py)2(BPE)Ru(bpy)2Cl](PF6)2 complex (bpy = 2,2′-bipyridine, BPE = trans-1,2-bis(4-pyridil)ethylene and py = pyridine) was assembled by the combination of an electroactive [Ru3O] moiety with a [Ru(bpy)2(BPE)Cl] photoactive centre, and its structure was determined using positive ion electrospray (ESI-MS) and tandem mass (ESI-MS/MS)
spectrometry. The [Ru3O(CH3COO)6(py)2(BPE)Ru(bpy)2Cl]2+ doubly charged ion of m/z 732 was mass-selected and subject to 15 eV collision-induced dissociation, leading to a specific dissociation pattern, diagnostic
of the complex structure. The electronic spectra display broad bands at 409, 491 and 692 nm ascribed to the [Ru(bpy)2(BPE)] charge-transfer bands and to the [Ru3O] internal cluster transitions. The cyclic voltammetry shows five reversible waves at −1.07 V, 0.13 V, 1.17 V, 2.91 V and
−1.29 V (vs SHE) assigned to the [Ru3O]−1/0/+1/+2/+3 and to the bpy0/−1 redox processes; also a wave is observed at 0.96 V, assigned to the Ru+2/+3 pair. Despite the conjugated BPE bridge, the electrochemical and spectroelectrochemical results indicate only a weak coupling
through the π-system, and preliminary photophysical essays showed the compound decomposes under visible light irradiation. 相似文献
3.
The ethylenediaminetetraacetate complex Li(H2O)3[Ga(Edta)] was synthesized and its crystal structure composed of octahedral (Ga(Edta)− anions connected to the Li(H2O)3+ ion through the oxygen atom was studied. Five of the six hydrogen atoms of water molecules are involved in weak hydrogen
bonds with the oxygen atoms of four Ga(Edta)− complexes, the complex anion is hydrogen-bonded to five water molecules. In addition, shortened contacts C(221)–H(22A)…O(112) between the Ga(Edta)− anions were found. As a result, the molecular packing in the crystal is determined by the three-dimensional lace of hydrogen
bonds. The results are compared with published data for the lithium salts of Bi(III), Sb(III), Fe(III), Ni(II), and Hg(II)
ethylenediaminetetraacetates. 相似文献
4.
I. E. Animitsa E. N. Dogodaeva S. S. Nokhrin O. A. Kosareva A. Ya. Neiman 《Russian Journal of Electrochemistry》2010,46(7):734-740
Perovskite phases Ba3In2ZrO8 and Ba4In2Zr2O11 with the nominal concentration of structural oxygen vacancies 1/9 and 1/12, respectively, were synthesized by solid-phase
and solution methods. X-ray diffraction showed cubic symmetry of both phases with the unit cell parameter a = 0.4193(2) and 0.4204(3) nm, respectively. The absence of superstructural lines resulted in the conclusion on statistical
arrangement of oxygen vacancies. Thermogravimetry and mass spectrometry proved that both phases can reversibly absorb water
from gas phase (pH2O = 2 × 10−2 atm) with observed correlation between the concentration of oxygen vacancies and amount of absorbed water. The total water
amount was up to 0.9 mol per formula unit or, if recalculated for perovskite unit ABO3, 0.3 and 0.23 mol H2O, respectively. The temperature curves of coductivity in the atmosphere with various partial water vapor pressures (pH2O = 3 × 10−5 and 2 × 10−2 atm) showed significantly higher conductivity and lower activation energy (0.52 eV) in humid atmosphere due to proton transfer.
The proton conductivity is up to 5 × 10−4 Ohm−1 cm−1 at 300°C for Ba3In2ZrO8 specimen. IR spectrometry showed that protons in the structure exist primarily in OH-groups. 相似文献
5.
Peter Klampfer Primož Benkič Maja Ponikvar Ana Rahten Antonija Lesar Adolf Jesih 《Monatshefte für Chemie / Chemical Monthly》2003,134(1):1-9
Summary. Hydrazinium(+2) fluoroarsenate(III) fluoride was prepared by the reaction of hydrazinium(+2) fluoride and liquid arsenic
trifluoride. N2H6AsF4F is stable at 273 K, but decomposes slowly at room temperature. N2H6AsF4F crystallizes in the orthorhombic space group Pnn2 with a = 774.0(2) pm, b = 1629.2(4) pm and c = 436.6(1) pm; V = 0.5506(3) nm3, Z = 4 and d
c
= 2.461 g cm−3. The structure consists of N2H6
2+ cations, AsF4
− anions, and F− anions and is interconnected by a hydrogen bonding network. Distorted trigonal-bipyramidal AsF4
− units are very weakly interconnected and form chains along the b axis. Bands in the Raman spectrum are assigned to the vibrations of N2H6
+2 cations and AsF4
− anions.
Corresponding author. E-mail: adolf.jesih@ijs.si
Received April 18, 2002; accepted July 15, 2002 相似文献
6.
A. N. Mansurova R. I. Gulyaeva V. M. Chumarev V. P. Mar’evich 《Journal of Thermal Analysis and Calorimetry》2010,101(1):45-47
Homogeneous manganocolumbite (MnNb2O6) was synthesized from Nb2O5 and MnO oxides. Powder sample was orthorhombic with unit cell parameters: α = 0.5766 nm, b = 1.4439 nm, c = 0.5085 nm and V = 0.4234 nm3. Heat capacity over the temperature range of 313–1253 K was measured in an inert atmosphere with combined thermogravimetry
and calorimetry using NETZSCH STA 449C Jupiter thermoanalyzer. Melting point was 1767 ± 3 K, enthalpy of melting was 144 ± 4 kJ mol−1. Experimental heat capacity of MnNb2O6 is fitted to polynomial C
pm = 221.46 + 3.03 · 10−3 T + −39.79 · 105 T
−2 + 40.59 · 10−6 T
2. 相似文献
7.
V. V. Drozdova E. A. Malinina L. V. Goeva I. N. Polyakova N. T. Kuznetsov 《Russian Journal of Inorganic Chemistry》2010,55(1):34-39
A method for the synthesis of the silver(I) complex with the closo-decaborate anion and triphenylphosphine [Ag2(Ph3P)2B10H10]
n
was developed and the structure of this complex was studied. The polymeric chain of the complex is formed with participation
of Ag(I) atoms, which coordinate the B10H102− anions through the apical (B(1)–B(2), B(9)–B(10)) and equatorial (B(3)–B(6), B(5)–B(8)) edges, the metalligand bonding occurring
through three-center two-electron bonds (MHB). The P atoms of two triphenylphosphine molecules are also incorporated in the
inner coordination sphere of the metal: the CN of the silver atom is 4 + 1. 相似文献
8.
Quantum-chemical calculations of the geometry and energies of nine possible isomers of 12-vertex cobaltacarborane CpCoC2B9H11 (1) were carried out by the DFT method (PBEPBE/DGDZVP/DGA1). Thermodynamic stability of the isomers increases with increasing
distance between the carbon atoms in the cage and is virtually independent of the position of the CpCo vertex. The relative
stabilities of the 1,2,3-(17.57 kcal mol−1), 1,2,4-(3.72 kcal mol−1), and 1,2,9-isomers of 1 (0 kcal mol−1) are similar to the corresponding values for the ortho (17.61 kcal mol−1), meta (3.21 kcal mol−1), and para isomers (0 kcal mol−1) of carborane C2B10H12. The results of the present study confirm a close similarity of the CpCo and BH fragments in metallacarborane chemistry.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1557–1559, July, 2005. 相似文献
9.
In the compound [Ni(Bptc)2(Bimb)2(H2O)2] (I), where H4Bptc is 3,3′,4,4′-biphenyltetracarboxylic acid; Bimb is 4,4′-bis(1-imidazolyl)biphenyl), Ni(II) has a distorted octahedral coordination geometry, which was bonded with two N atoms from two
Bimb ligands, two O atoms from two H2Bptc2− ligands and two water O atoms. The crystal structure of compound I is stabilized by the π-π-stacking and hydrogen bonds interaction. 相似文献
10.
Danielle M. Chisholm J. Scott McIndoe Gabriella Bodizs Wee Han Ang Rosario Scopelliti Paul J. Dyson 《Journal of Cluster Science》2007,18(1):303-318
Reaction of [Ru6C(CO)16]2− with an excess of AgX (X = Cl, Br or I) affords heteronuclear clusters of formula [{Ru6C(CO)16Ag2X}2]2− in 80% yield, which for X = I and X = Br/Cl were crystallographically characterised. The formation of the cluster was followed
in solution using electrospray ionisation mass spectrometry (ESI-MS), which revealed the presence of a wide range of clusters
with the general formula [{Ru6C(CO)16}
x
Ag
y
X
z
](2x−y+z)− where x = 1 or 2, y = 1, 2, 3 or 4 and z = 0, 1 or 2. The high yield of the product despite the evident complicated solution speciation is attributed to selective
crystallisation of the observed compound driving the equilibrium toward this product. 相似文献
11.
J. Leitner M. Hampl K. Růžička M. Straka D. Sedmidubský P. Svoboda 《Journal of Thermal Analysis and Calorimetry》2008,91(3):985-990
The heat capacity and the enthalpy increments of strontium metaniobate SrNb2O6 were measured by the relaxation method (2-276 K), micro DSC calorimetry (260-320 K) and drop calorimetry (723-1472 K). Temperature
dependence of the molar heat capacity in the form C
pm=(200.47±5.51)+(0.02937±0.0760)T-(3.4728±0.3115)·106/T
2 J K−1 mol−1 (298-1500 K) was derived by the least-squares method from the experimental data. Furthermore, the standard molar entropy
at 298.15 K S
m0 (298.15 K)=173.88±0.39 J K−1 mol−1 was evaluated from the low temperature heat capacity measurements. The standard enthalpy of formation Δf
H
0 (298.15 K)=-2826.78 kJ mol−1 was derived from total energies obtained by full potential LAPW electronic structure calculations within density functional
theory. 相似文献
12.
V. L. Lobachev G. P. Zimtseva Ya. V. Matvienko E. S. Rudakov 《Theoretical and Experimental Chemistry》2007,43(1):44-49
Data obtained for the kinetics of oxidation of diethyl sulfide (Et2S) by hydrogen peroxide in aqueous solution catalyzed by boric acid indicate that monoperoxoborates B(O2H)(OH)
3
−
and diperoxoborates B(O2H)2(OH)
2
−
are the active species. The rates of the reactions of Et2S with B(O2H)(OH)
3
−
and B(O2H)2(OH)
2
−
are 2.5 and 100 times greater than with H2O2.
__________
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 43, No. 1, pp. 38–42, January–February, 2007. 相似文献
13.
Rollie J. Myers 《Journal of solution chemistry》2007,36(3):395-403
We have measured the second acid dissociation constant, K
2a
, at several ionic strengths for hydrogen telluride (H2Te) using the Charge Transfer to Solvent (CTTS) uv spectra of its anions HTe− and Te2−. Since it is produced in our solutions, we have also determined the spectra of Te2
2− both in the uv and in the visible regions. At 25 ∘C, K
2a
= (1.28 ± 0.02) × 10−12 by extrapolation to zero ionic strength. Its value at an ionic strength equal to 0.5 mol.dm-3 was estimated to be (8.7 ± 0.2) × 10−12. The solution thermodynamics of these species are also discussed and comparisons are made to related acids. 相似文献
14.
A. D. Chervonnyi 《Russian Journal of Inorganic Chemistry》2010,55(4):556-559
The A1, O, AlO, A12O, Al2O2, WO2, and WO3, partial pressures in the vapor over Al2O3 in a tungsten Knudsen effusion cell between 2300 and 2600 K were derived from A1+, O+, AlO+, A12O+, Al2O2+, WO2+, and WO3+, ion intensities. The mass spectrometer was calibrated against the equilibrium constant of the WO3(g) = WO2(g) + O(g) reaction. Refined values of the ionization cross sections of AlO and A12O2 were used in the partial pressure calculations. The enthalpies of atomization of aluminum suboxides were determined to be
Δat
H
o(AlO, g, 0) = 510.7 ± 3.3 kJ mol−1, Δat
H
o(Al2O, g, 0) = 1067.2 ± 6.9 kJ mol−1, and Δat
H
o(Al2O2, g, 0) = 1556.7 ± 9.9 kJ mol−1. 相似文献
15.
H. M. Ye N. Ren H. Li J. J. Zhang S. J. Sun L. Tian 《Journal of Thermal Analysis and Calorimetry》2010,101(1):205-211
The complex of [Nd(BA)3bipy]2 (BA = benzoic acid; bipy = 2,2′-bipyridine) has been synthesized and characterized by elemental analysis, IR spectra, single
crystal X-ray diffraction, and TG/DTG techniques. The crystal is monoclinic with space group P2(1)/n. The two–eight coordinated Nd3+ ions are linked together by four bridged BA ligands and each Nd3+ ion is further bonded to one chelated bidentate BA ligand and one 2,2′-bipyridine molecule. The thermal decomposition process
of the title complex was discussed by TG/DTG and IR techniques. The non-isothermal kinetics was investigated by using double
equal-double step method. The kinetic equation for the first stage can be expressed as dα/dt = A exp(−E/RT)(1 − α). The thermodynamic parameters (ΔH
≠, ΔG
≠, and ΔS
≠) and kinetic parameters (activation energy E and pre-exponential factor A) were also calculated. 相似文献
16.
Matthias Weil Franz Werner Frank Kubel 《Monatshefte für Chemie / Chemical Monthly》2002,133(3):267-275
Summary. Single crystals of MgAl2F8(H2O)2 have been obtained under hydrothermal conditions (250°C, 14 d) from a starting mixture of AlF3 and MgAlF5(H2O)2 in a 5% (w/w) HF solution. The crystal structure has been determined and refined from single crystal data (Fmmm (#69), Z = 4, a = 7.2691(7), b = 7.0954(16), c = 12.452(2) ?, 281 structure factors, 27 parameters, R(F
2 > 2σ (F
2)) = 0.0282, wR(F
2 all) = 0.0885). The obtained crystals were systematically twinned according to (010/100/001) as twinning matrix, reflecting
the pseudo-tetragonal metric. The crystal structure is composed of perowskite-type layers built of corner sharing AlF6 octahedra with an overall composition of AlF4
− which are connected via common fluorine atoms of [MgF4/2(H2O)2/1] octahedra. Group-subgroup relations of MgAl2F8(H2O)2 to WO3(H2O)0.33 and to other M(II)M(III)2 F8(H2O)2 structures are briefly discussed. Above 570°C, MgAl2F8(H2O)2 decomposes under elimination of water into α-AlF3, β-AlF3, and MgF2.
Received October 29, 2001. Accepted (revised) December 6, 2001 相似文献
17.
Ji-min Yang Yan Yao Run-zhi Zhang Ai-de Sun Bao-hui Li Hong-zhi Lu Qi-ying Xia 《Journal of solution chemistry》2009,38(4):429-439
Osmotic coefficients and water activities for the Li2B4O7+LiCl+H2O system have been measured at T=273.15 K by the isopiestic method, using an improved apparatus. Two types of osmotic coefficients, φ
S and φ
E, were determined. φ
S is based on the stoichiometric molalities of the solute Li2B4O7(aq), and φ
E is based on equilibrium molalities from consideration of the equilibrium speciation into H3BO3,B(OH)4− and B3O3(OH)4−. The stoichiometric equilibrium constants K
m
for the aqueous speciation reactions were estimated. Two types of representations of the osmotic coefficients for the Li2B4O7+LiCl+H2O system are presented with ion-interaction models based on Pitzer’s equations with minor modifications: model (I) represents
the φ
S data with six parameters based on considering the ion-interactions between three ionic species of Li+, Cl−, and B4O72−, and model (II) for represents the φ
E data based on considering the equilibrium speciation. The parameters of models (I) and (II) are presented. The standard deviations
for the two models are 0.0152 and 0.0298, respectively. Model (I) was more satisfactory than model (II) for representing the
isopiestic data. 相似文献
18.
E. Vessally M. Nikoorazm A. Esmaili H. Ghoudarzi Afshar 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2011,85(4):631-635
Thermal internal energy gaps, ΔE
s−t; enthalpy gaps, ΔH
s−t; Gibbs free energy gaps, ΔD
s−t, between singlet (s) and triplet (t) states of R2C4H2M (M = C, Si, and Ge) were calculated at B3LYP/6-311++G** level of theory. The ΔG
s−t of R2C4H2C was increased in the order (in kcal/mol): R = −CH3 (−10.51) > −H (−9.59) > i-Pr (−9.51) > t-Bu (−8.98). While, the ΔG
s−t of R2C4H2Si and R2C4H2Ge were increased in the order (in kcal/mol): −CH3 (17.01) > i-Pr (15.30) > −H (15.26) > t-Bu (14.35) and -H (22.79) > −CH3 (22.69) > i-Pr (21.66) > t-Bu (21.01), respectively. 相似文献
19.
Y. R. Zhao J. X. Dong Y. Liu S. S. Qu 《Journal of Thermal Analysis and Calorimetry》2007,90(2):565-568
The two complexes, [RE(Gly)4(Im)(H2O)](ClO4)3(s)(RE = Eu, Sm), have been synthesized and characterized. The standard molar enthalpies of reaction for the following reactions,
RECl3·6H2O(s)+4Gly(s)+Im(s)+3NaClO4(s) = =[RE(Gly)4(Im)(H2O)](ClO4)3(s)+3NaCl(s)+5H2O(l), were determined by solution-reaction colorimetry. The standard molar enthalpies of formation of the two complexes at
T = 298.15 K were derived as Δf
H
mΘ {Eu(Gly)4(Im)(H2O)}(ClO4)3(s)} = = −(3396.6±2.3) kJ mol−1 and Δf
H
mΘ {Sm(Gly)4(Im)(H2O)}(ClO4)3(s)} = −(3472.7±2.3) kJ mol−1, respectively. 相似文献
20.
Jiaoyun Xia Yongxian Wang Gucai Li Junfeng Yu Duanzhi Yin 《Journal of Radioanalytical and Nuclear Chemistry》2009,279(1):245-252
In this paper, we investigated three ligand systems, symmetric and asymmetric pyridyl-containing tridentate ligands (L1NH2 = (bis(2-pyridylmethyl)-amino)-ethylamine, L2H = (bis(2-pyridylmethyl)-amino)-acetic acid, L3NH2 = [(6-amino-hexyl)-pyridyl-2-methyl-amino]-acetic acid) as bifunctional chelating agents for labeling biomolecules. These
ligands reacted with the precursor fac-[188Re(CO)3(H2O)3]+ and yielded the radioactive complexes fac-[188Re(CO)3L] (L = three ligands), which were identified by RP-HPLC. The corresponding stable rhenium tricarbonyl complexes (1–3) were
allowed for macroscopic identification of the radiochemical compounds. 188Re tricarbonyl complexes, with log P
o/w
values ranging from −1.36 to −0.32, were obtained with yields of ≥90% using ligand concentrations within the 10−6−10−4M range. Challenge studies with cysteine and histidine revealed the high stability properties of these radioactive complexes,
and biodistribution studies in normal mice indicated a fast rate of blood clearance and high rate of total radioactivity excretion,
primarily through the renal-urinary pathway. In summary, these asymmetric and symmetric pyridyl-containing tridentate ligands
are potent bifunctional chelators for the future biomolecules labeling of fac-[188Re(CO)3(H2O)3]+. 相似文献