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1.
O. P. Charkin 《Russian Journal of Inorganic Chemistry》2009,54(4):601-610
The electronic and geometric structures and the energetic characteristics of isolated dimeric molecules and positive ions
of ferriporphyrin analogues (MC34H31O4N4)20,+ and corresponding monomers MC34H31O4N40,+ with 3d-metal atoms M = Sc-Ni in states with different multiplicities were calculated by the density functional theory B3LYP method
with the Gen-1 = 6-31G*(Fe) + 6-31G(C,H,N,O) basis set. Their energies were refined with the use of the extended basis set
Gen-2 = 6-311+G*(Fe) + 6-31G*(C,H,N,O). The computation results were compared with the analogous calculated data on the dimers
of heme analogues (MC34H32O4N4)20,+ and MC34H32O4N40,+ with the same M atoms. The behavior of the above-mentioned properties was analyzed in going along the 3d series, upon ionization and a change in multiplicity, and in other related series. Trends were traced in the calculated energies
D
1 of dissociation of the ferriporphyrin analogue dimers into monomers, (MC34H31O4N4)20,+ → MC34H31O4N40,+MC34H31O4N40, and in the energies D
2 of removal of two hydrogen atoms from heme analogue dimers resulting in ferriporphyrin analogues, (MC34H32O4N4)20,+ → (MC34H31O4N4)20,+ + 2H. It was shown that, in going along the 3d series, the D
1 energy rapidly decreases from ∼210 kcal/mol for M = Sc to a few tens of kcal/mol for M = Ni, with a small minimum for Mn
and a small maximum for Fe, as the energy of the pair of broken covalent (polar) bonds M-O decreases. Conversely, the D
2 energy increases rapidly and rather monotonically from ∼45 kcal/mol for M = Sc to ∼135 kcal/mol for M = Fe, as the difference
between the energies of the pair of forming covalent bonds M-O and the pair of broken donor-acceptor bonds M ← O decreases.
For the positive ions, the D
1 and D
2 values are, as a rule, 5–10 kcal/mol higher than those for the parent neutral analogues. The character of the spin density
distribution in states with different multiplicities was considered.
Original Russian Text ? O.P. Charkin, 2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 4, pp. 655–665. 相似文献
2.
O. P. Charkin N. M. Klimenko D. O. Charkin S. H. Lin 《Russian Journal of Inorganic Chemistry》2007,52(7):1088-1097
The electronic and geometric structures and the dissociation energies of the isolated molecule of heme dimer (heme)2 = (FeC34H32O4N4)2 and its ion (heme)
2
+
= (FeC34H32O4N4)
2
+
in the states with different multiplicities have been calculated by the density functional theory B3LYP method with the Gen-1
= 6-31G*(Fe) + 6-31G(C,H,N,O) and Gen-2 = 6-311++G*(Fe) + 6-31G*(C,H,N,O) basis sets. The computation results are compared
with the analogous calculated data on monomeric heme and hemin+, as well as the previously considered dimeric ferriporphyrin X molecule and ion FeC34H31O4N4)
2
0, +
. In the heme dimer cation (heme)
2
+
, which is identified in mass spectra, the rings are linked with each other by a pair of Fe carbonyl bridges Fe⋯Ob = C(OH) and a pair of hydrogen bridges OHb⋯N. According to the calculations, the most favorable state for (heme)
2
+
is the sextet in which five unpaired electrons are approximately uniformly distributed over the metal atoms, whereas the
states with higher multiplicities 8 and 10 are, respectively, 0.15 and 0.20 eV higher on the energy scale. For the neutral
dimer (heme)2, the quintet is favorable in which each of the two Fe atoms has two unpaired electrons, and the states with the higher multiplicities
7 and 9 are only 0.10–0.15 eV higher. The calculated energies of dissociation D of the dimers into monomers point to a rather high stability of the (heme)
2
+
(D ∼ 1.4 1.4eV) and to a low stability of the neutral dimer (heme)2 (D ∼ 0.3 eV). The R(Fe⋯Ob) distances in the bridges in (heme)
2
+
are 0.2–0.4 ? shorter than in (heme)2. The trends in the behavior of the energetic and structural characteristics of the dimers (R(Fe-N), displacements of Fe atoms from the porphyrin ring plane, character of ring distortions, etc.) associated with the
involvement of the
and
AOs of Fe atoms in bonding, as well as the spin density distribution over the Fe atoms and the rings, are analyzed as a function
of the multiplicity and charge of the system. Differences in the character of interaction of the heme and ferriporphyrin dimers
with molecular oxygen are discussed.
Original Russian Text ? O.P. Charkin, N.M. Klimenko, D.O. Charkin, S.H. Lin, 2007, published in Zhurnal Neorganicheskoi Khimii,
2007, Vol. 52, No. 7, pp. 1166–1174. 相似文献
3.
4.
采用从头计算MP2和CIS方法分别优化等电子双核d8配合物[Pt2(P2O4H2)4]4-和[Pt2(P2O4CH4)4]4-的基态和激发态结构。结果表明基态Pt-Pt距离分别为0.290 5和0.298 7 nm,与实验的0.292 5和0.298 0 nm符合。NBO计算的Pt-Pt键级以及Pt原子间伸缩振动说明Pt-Pt相互作用具有吸引本质。CIS计算揭示电子激发到Pt-Pt的σ(pz)成键轨道使得相互作用增强。保持激发态几何,含时密度泛函理论(TD-DFT)计算的溶液发射分别为449和475 nm,与实验值512和510 nm接近。 相似文献
5.
6.
Suhua Shi 《Journal of solid state chemistry》2004,177(11):4183-4187
A new vanadium(III) phosphite, (C4H8N2H4)0.5(C4H8N2H3)[V4(HPO3)7(H2O)3]1.5H2O, has been synthesized hydrothermally by using V2O5, H3PO3 as reactants, piperazine as the structure-directing agent. The as-synthesized product was characterized by powder X-ray diffraction, IR spectroscopy, inductively coupled plasma analysis, thermogravimetric analysis, and SQUID magnetometer. Single-crystal X-ray diffraction analysis shows that the title compound crystallized in the trigonal space group (No. 165) with the parameters: , , and Z=4. Its structure is built up by alternation of octahedral VO6 or VO5(H2O) and pseudo-pyramidal HPO3 units to form infinite 2D layers, and these layers are interconnected by sharing vertex-oxygen with octahedral VO6 units to generate a 3D open-framework structure with 12-membered ring channels in a and b directions, respectively, where there exist entrapped diprotonated and mono-protonated piperazine cations, and water molecules. Magnetic measurement indicates that paramagnetic behavior is observed down to 4 K. 相似文献
7.
在140℃下,以3-溴-4-甲基苯甲酸和咪唑为配体,通过水热法在甲醇/水混合溶剂中反应24 h合成了锌(Ⅱ)配合物Zn(C3H4N2)2(C8H6O2Br)2。通过元素分析、红外光谱、热重分析和X射线粉末衍射对配合物进行了结构表征,同时用X射线单晶衍射分析确定了其晶体结构。结果表明,其晶体属单斜晶系,空间群为C2/c,晶胞参数:a=13.257(3),b=9.765(2),c=20.494(4),β=107.79(3)°,V=2526.3(9)3,Dc=1.655g·cm-3,μ=4.170mm-1,F(000)=1248,Z=4,最终残差因子R1=0.0552,wR2=0.1378。配合物为单核结构,中心锌(Ⅱ)离子与来自2个3-溴-4-甲基苯甲酸根的2个O原子及2个咪唑分子的2个N原子配位,形成了畸变的四方锥几何体。晶体内,分子间则通过N—H…O氢键作用在ab面形成了层状结构。研究了配合物的发光性质。 相似文献
8.
9.
Sergey V. Krivovichev 《Journal of solid state chemistry》2003,170(1):106-117
Two new mixed organic-inorganic uranyl molybdates, (C6H14N2)3[(UO2)5(MoO4)8](H2O)4 (1) and (C2H10N2)[(UO2)(MoO4)2] (2), have been obtained by hydrothermal methods. The structure of 1 [triclinic, , Z=1, a=11.8557(9), b=11.8702(9), c=12.6746(9) Å, α=96.734(2)°, β=91.107(2)°, γ=110.193(2)°, V=1659.1(2) Å] has been solved by direct methods and refined on the basis of F2 for all unique reflections to R1=0.058, which was calculated for the 5642 unique observed reflections (|Fo|?4σF). The structure contains topologically novel sheets of uranyl square bipyramids, uranyl pentagonal bipyramids, and MoO4 tetrahedra, with composition [(UO2)5(MoO4)8]6−, that are parallel to (−101). H2O groups and 1,4-diazabicyclo [2.2.2]-octane (DABCO) molecules are located in the interlayer, where they provide linkage of the sheets. The structure of 2 [triclinic, , Z=2, a=8.4004(4), b=11.2600(5), c=13.1239(6) Å, α=86.112(1)°, β=86.434(1)°, γ=76.544(1)°, V=1203.14(10) Å] has been solved by direct methods and refined on the basis of F2 for all unique reflections to R1=0.043, which was calculated for 5491 unique observed reflections (|Fo|?4σF). The structure contains topologically novel sheets of uranyl pentagonal bipyramids and MoO4 tetrahedra, with composition [(UO2)(MoO4)2]2−, that are parallel to (110). Ethylenediamine molecules are located in the interlayer, where they provide linkage of the sheets. All known topologies of uranyl molybdate sheets of corner-sharing U and Mo polyhedra can be described by their nodal representations (representations as graphs in which U and Mo polyhedra are given as black and white vertices, respectively). Each topology can be derived from a simple black-and-white graph of six-connected black vertices and three-connected white vertices by deleting some of its segments and white vertices. 相似文献
10.
F. Charbonnier 《Thermochimica Acta》1974,10(3):285-298
Two new salts of malonic acid have been prepared: the copper(II) malonate tetrahydrate and the copper(II)-ammonium double malonate. Their study by thermal analysis (TG and DTA) leads to the following results:Cu(C3H2O4)·4H2O: the dehydration is rather complex and it is only under careful conditions that an intermediate hydrate Cu(C3H2O4)·3H2O could be traced. At about 170°C the dehydration is not ended (the salt holds yet about 0.15H2O) and the anhydrous salt occurs only at about 240°C. It decomposes immediately leading to residues the composition of which depends upon the surrounding atmosphere; the part played by the gas given off is discussed.Cu(NH4)2(C3H2O4)2: this salt melts and decomposes simultaneously at about 190°C. During the decomposition the copper nitride Cu3N forms as intermediate compound (as well as copper metal). Concerning the final residues of the decomposition the results and the conclusions are the same as the ones of the previous case. 相似文献
11.
O. A. Kirichenko G. Z. Kaziev S. Holguin Quinones S. A. Ivanov A. M. Koroteev E. A. Solov’eva A. De Ita Torre 《Russian Journal of General Chemistry》2012,82(2):175-179
The di(1,3,7-trimethylpurine-2,6-dione) dihydrogen 12-tungstosilicate (C8N4O2H11)2H2SiW12O40 (I) was synthesized and studied using chemical methods, IR and 1H NMR spectroscopy, X-ray phase analysis, and the thermogravimetry technique. 相似文献
12.
V.A. Bhirud P.W. Kletnieks J.F. Haw M.M. Olmstead 《Journal of organometallic chemistry》2007,692(10):2107-2113
We report a new synthesis and characterization of Ir(C2H4)2(C5H7O2) [(acetylacetonato)-bis(η2-ethene)iridium(I)], prepared from (NH4)3IrCl6 · H2O in a yield of about 45%. The compound has been characterized by X-ray diffraction crystallography, infrared, Raman, and NMR spectroscopies and calculations at the level of density functional theory. Ir(C2H4)2(C5H7O2) is isostructural with Rh(C2H4)2(C5H7O2), but there is a substantial difference in the ethylene binding energies, with Ir-ethylene having a stronger interaction than Rh-ethylene; two ethylenes are bound to Ir with a binding energy of 94 kcal/mol and to Rh with a binding energy of 70 kcal/mol. 相似文献
13.
The geometrical parameters, normal vibration frequencies, and thermochemical characteristics of the Na2Cl+, NaCl
2
−
, Na3Cl
2
+
, and Na2Cl
3
−
ions in saturated vapors over sodium chloride were calculated by the ab initio methods including electron correlation. According to calculations, the Na2Cl+ and NaCl
2
−
triatomic ions have a linear equilibrium D
∞h
configuration. The pentaatomic ions can exist in the form of the D
∞h
linear isomer, C
2v
planar cyclic isomer, or D
3h
bipyramidal isomer. At ∼1000 K the Na3Cl
2
+
and Na2Cl
3
−
ions exist predominantly in the form of the linear isomers. The energies and enthalpies of the ion-molecule reactions involving
the above ions were calculated. The formation enthalpy of the ions Δf
H
0(0 K) was determined: 230 ± 2 kJ/mol (Na2Cl+), −96 ± 4 kJ/mol (Na2Cl
3
−
), −616 ± 2 kJ/mol (NaCl
2
−
), and −935 ± 4 kJ/mol (Na2Cl
3
−
).
Original Russian Text Copyright ? 2007 by T. P. Pogrebnaya, A. M. Pogrebnoi, and L. S. Kudin
__________
Translated from Zhurnal Strukturnoi Khimii, Vol. 48, No. 6, pp. 1053–1061, November–December, 2007. 相似文献
14.
15.
R. Schwesinger K. Piontek W. Littke O. Schweikert H. Prinzbach C. Krüger Y.-H. Tsay 《Tetrahedron letters》1982,23(24):2427-2430
According to X-ray crystal structure analyses “cis-benzenetrisimine” () and “cis-benzenetrioxide” () act as tridentate ligands in their 2:1- and 4:1-complexes (Co(C6H9N3)2(NO3)3) and (Ba(C6H6O3)4(ClO4)2), resp. The latter is the rare example of an organic complex with the (approximate) T-symmetry. 相似文献
16.
T. M. Polyanskaya M. K. Drozdova V. V. Volkov K. G. Myakishev 《Journal of Structural Chemistry》2009,50(2):368-372
A new compound [MNII(Phen)3]2+(B6H7)2− is synthesized; its crystal structure is studied by XRD at 100 K. Crystallographic data: C36H38B12N6Mn, M = 739.39, triclinic symmetry, space group P
, unit cell parameters: a = 10.3131(3) ?, b = 13.4839(4) ?, c = 15.1132(4) ?; α = 97.696(1)°, β = 108.324(1)°, γ = 102.211(1)°; V = 1903.9(1) ?3, Z = 2, d
calc = 1.290 g/cm3. The structure is solved by direct and Fourier methods and refined by full-matrix LSM in the anisotropic (isotropic for hydrogen
atoms) approximation to the final factor R
1 = 0.036 for 10169 I
hkl
≥ 2σ
I
(Bruker-Nonius X8 APEX CCD diffractometer, λMoK
α). The structure contains two crystallographically different anions.
Original Russian Text Copyright ? 2009 by T. M. Polyanskaya, M. K. Drozdova, V. V. Volkov, and K. G. Myakishev
__________
Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 2, pp. 381–385, March–April, 2009. 相似文献
17.
D. P. Domonov S. I. Pechenyuk N. L. Mikhailova A. T. Belyaevskii 《Russian Journal of Inorganic Chemistry》2007,52(7):1027-1032
The thermolysis of the complexes [Co(NH3)6]2C2O4[Cu(C2O4)2]2 (I) and [Co(NH3)6]Cl[Cu(C7H4O3)2] (II) in air and hydrogen at 200, 350, and 500°C and the composition and properties of the thermolysis products are considered.
The oxidative thermolysis of the complexes yields mixtures of cobalt and copper oxides, including mixed ones. The reductive
thermolysis of the complexes yields a Co + Cu bimetallic powder in the case of compound I and a Co + Cu + C powder in the
case of compound II. The thermal behavior of the complexes is governed by the nature of the ligand coordinated to the copper
atom. The observed data are explicable in terms of the properties of this ligand. The chemistry of the oxidative and reductive
thermolysis is discussed.
Original Russian Text ? D.P. Domonov, S.I. Pechenyuk, N.L. Mikhailova, A.T. Belyaevskii, 2007, published in Zhurnal Neorganicheskoi
Khimii, 2007, Vol. 52, No. 7, pp. 1104–1110. 相似文献
18.
V. A. Zasukha A. P. Shpak V. V. Trachevskii E. V. Urubkova 《Journal of Structural Chemistry》2005,46(3):393-403
Group-theoretical analysis and molecular orbital methods were used to obtain (in analytical form) the electronic structure
and reactivity of the PO
4
3−
, SO
4
2−
and P2O
7
4−
, S2O
7
2−
anions. The reactivity of the anions is dictated by the availability of lone electron pairs on the top quasidegenerate MOs
in the form of linear combinations of group orbitals from atomic orbitals (AOs) of peripheral oxygen atoms for PO
4
3−
, SO
4
2−
and the central (bridging) atom for P2O
7
4−
, S2O
7
2−
. These electron pairs are responsible for the donor-acceptor interactions during complexation, clustering, and other (addition,
substitution, etc.) reactions.
Original Russian Text Copyright ? 2005 V. A. Zasukha, A. P. Shpak, V. V. Trachevskii, and E. V. Urubkova
__________
Translated from Zhurnal Strukturnoi Khimii, Vol. 46, No. 3, pp. 405–415, May–June, 2005. 相似文献
19.
Richard D. Adams Burjor Captain Wei Fu Mark D. Smith Lei Zhu 《Journal of Cluster Science》2006,17(1):87-95
Two new compounds Pd2Os3(CO)12
, 13 and Pd3Os3(CO)12
, 14 have been obtained from the reaction of
with Os3(CO)12 at room temperature. The products were formed by the addition of two and three
groups to the Os–Os bonds of Os3(CO)12. Compounds 13 and 14 interconvert between themselves by intermolecular exchange of the
groups in solution. Compounds 13 and 14 have been characterized by single crystal X-ray diffraction analyses.Dedicated to Professor Brian F. G. Johnson on the occasion of his retirement – 2005. 相似文献
20.
Ray-Kuang Chiang Niang-Tsu ChuangChing-Shuei Wur Mong-Fu ChongChung-Rong Lin 《Journal of solid state chemistry》2002,166(1):158-163
A new hybrid organic-inorganic three-dimensional compound, [Co4(OH)2(H2O)2](C4H11N2)2[C6H2(CO2)4]2·3H2O 1, has been synthesized via hydrothermal reactions and characterized by single-crystal X-ray diffraction, infrared spectroscopy, thermogravimetric analysis, and magnetic techniques. Compound 1 crystallizes in the monoclinic space group P21/n (no. 14) with a=6.3029(9) Å, b=16.413(2) Å, c=17.139(2) Å, β=98.630(2)°, V=1735.0(4) Å3, Z=2. Compound 1 contains tetranuclear Co4(μ3-OH)2(H2O)2 clusters that are inter-linked by pyromellitate bridging ligands into a three-dimensional structure containing one-dimensional tunnels along the a-axis with water and pendant monoprotonated piperazine molecules in the center. The variable temperature magnetic susceptibility was measured from 2 to 300 K at 5000 Oe showing a predominantly anti-ferromagnetic interaction in 1, and the field dependence of magnetization was measured at 2, 5, 15, and 20 K indicating the competition of magnetic interactions in the tetranuclear centers. 相似文献