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1.
The molecular structure of 23,24,25,26,27,29,30-heptamethyl-19,28-oxahexacyclo[15.13.18.017,18.013,14.08,9.05,10]tetracos-3-yl acetate III. Compound III C32H52O3 crystallizes in the monoclinic crystal system with the unit cell parameters a = 13.265(15) ?, b = 6.481(7) ?, c = 32.274(4) ?, β = 99.333(2)°, space group C2, Z = 4, d = 1.176 g/cm3.
Original Russian Text Copyright ? 2009 by N. I. Medvedeva, O. B. Flechter, and A. A. Korlyukov
__________
Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 2, pp. 399–401, March–April, 2009. 相似文献
2.
The synthesis of methyl-10,14,19,19-tetramethyl-4-oxo-20-oxahexacyclo[15.3.1.16.18.06.15.09.14017.21] docosane-10-carboxylate III is performed and its molecular structure is determined. Compound III C27H40O4 crystallizes in the monoclinic system with the cell parameters as follows: a = 12.8081(11) ?, b = 7.0384(6) ?, c = 12.8904(12) ?, β = 105.828(2)o, P21 space group, Z = 2, d = 1.273 mg/m3. 相似文献
3.
The results of quantum chemical calculations of the electronic structure and geometry of octahedral clusters [Mo6S8(CN)6]6−, [Mo6Se8(CN)6]6−, [Re6S8(CN)6]4−, and Rh6(CO)16 by the ab initio SCF (RHF) and DFT (B3LYP) methods with various basis sets are presented. The electronic states of the clusters under study
in ideal spherically symmetric potential were classified in the orbital quantum number l (1s, 1p, 1d, 1f, 1g, 1h, 1i), l = 0–6. In real crystal field with Oh symmetry these states are split. The calculated new electronic states were matched to the irreducible representations of
the point symmetry group Oh. The polarizabilities of the compounds considered are 55–65 Å3. A new model for the electronic structure of octahedral clusters containing M6 groups was proposed. The model is based on the idea of free electrons moving in spherically symmetric potential field.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2617–2624, December, 2005. 相似文献
4.
V. F. Mironov E. N. Varaksina D. A. Tatarinov A. A. Shtyrlina A. B. Dobrynin I. A. Litvinov 《Russian Journal of General Chemistry》2008,78(2):192-196
2,2,2,6-Tetrachloro-4-phenylbenzo[e][1,2]oxaphosphinine and 2,2,6-trichloro-4-phenylbenzo[e][1,2λ5]-oxaphosphinin-2-ylium hexachlorophosphate were prepared by treatment of 2,6-dichloro-4-phenylbenzo[e][1,2λ5]-oxaphosphinine 2-oxide with phosphorus pentachloride. The structure of the latter compound was proved by means of X-ray
diffraction analysis.
Original Russian Text ? V.F. Mironov, E.N. Varaksina, D.A. Tatarinov, A.A. Shtyrlina, A.B. Dobrynin, I.A. Litvinov, 2008,
published in Zhurnal Obshchei Khimii. 2008, Vol. 78, No. 2, pp. 210–215. 相似文献
5.
I. E. Smirnova E. V. Tret’yakova O. B. Kazakova K. Yu. Suponitsky 《Journal of Structural Chemistry》2010,51(6):1208-1210
Methyl 20-isopropyl-15(E)-hydroxyimino-5,9-dimethyl-18-oxahexacyclo[12.4.0.22,13.118,20.05,10.04,13]-heneicosane-9-carboxylate is synthesized and its molecular structure is determined. Compound IIa of C27H41NO4 crystallizes in the acentric P21 space group with the following unit cell parameters: a = 7.6511(7) ?,b = 12.0698(11) ?, c = 12.9182(12) ?, β = 95.257(2)°. 相似文献
6.
A. I. Kalashnikov S. V. Sysolyatin G. V. Sakovich I. A. Surmacheva V. N. Surmachev Yu. T. Lapina 《Russian Chemical Bulletin》2009,58(10):2164-2168
The debenzylation of 2,6,8,12-tetraacetyl-4,10-dibenzyl-2,4,6,8,10,12-hexaazatetra-cyclo[5.5.0.03,11.05,9]dodecane by catalytic hydrogenolysis in a mixture of HCOOH with other RCOOH (R = Me, Et, Pri) is accompanied by the N-formylation of the liberated secondary amino groups. The alkaline hydrolysis of the obtained products makes it possible to
remove the formyl groups with the retention of the acetyl groups. 相似文献
7.
Pl. Muthuramalingam 《Journal of Chemical Sciences》1994,104(4):705-714
OnX =L
2(R
n), letQ = (Q
1,Q
2,…,Q
n) andP = (P
1,P
2, …,P
n) be the operators given by (Q
jf) (x) =x
jf(x),P
j = - i∂/∂x
j. For anyC
∞ functionh:R
n →R putH
0 =h(P) andH =H
0 + (1 +Q
2)-δ, where δ > 1/2. By the method of scattering theory we prove thatH
ac, the absolutely continuous part ofH is unitarily equivalent toH
0 when (a)n = 1 and (b) forn ≥ 2, whenh is in a large class of polynomials. It is conjectured that the results are true for any polynomialh. We use the techniques of Enss’ method and the idea of bound states for momentum. 相似文献
8.
M. H. Soorgi G. H. Rounaghi M. S. Kazemi 《Russian Journal of General Chemistry》2008,78(10):1866-1871
The complex formation between Na+, K+, Cs+, Rb+ and Tl+ metal cations with macrocyclic ligand, dicyclohexyl-18-crown-6 (DCH18C6) was studied in acetonitrile-water (AN-H2O) binary systems at different temperatures using conductometric method. DCH18C6 forms 1:1 complexes with these metal cations.
The stability constants of the complexes were obtained from fitting of molar conductivity curves using a computer program
Genplot. The results show that the selectivity order of DCH18C6 for the metal cations in acetonitrile-water mixtures (AN =
25.3 and 50.4 mol %) is: Tl+ > K+ > Rb+ > Cs+ > Na+. A non-linear behaviour was observed between the log K
f of the complexes versus the composition of the mixed solvent which it related to changes of acidity, basicity, polarity and
also polarizability of AN-H2O mixtures with the composition of this binary solution. The values of standard enthalpy changes (ΔH
s0) for complexation reactions were obtained from the slope of the van’t Hoff plots and the changes in the standard entropy
(ΔS
s0) were calculated from the relationship: ΔG
s,298.150 = ΔH
s0 − 298.15ΔS
s0. The obtained results show that in most cases, the complexes are enthalpy stabilized but entropy destabilized.
Original Russian Text ? M.H. Soorgi, G.H. Rounaghi, M.S. Kazemi, 2008, published in Zhurnal Obshchei Khimii, 2008, vol. 78,
No. 10, pp. 1627–1632. 相似文献
9.
C. Amiot 《Chemical physics letters》1981,83(1):40-43
The emission spectrum of NO excited by electric discharge has been recorded with a high-resolution Fourier transform interferometer. Strong perturbations are observed in the spectrum of the transition M2Σ+→ E2Σ+ (0—0), due to mixing of the Rydberg state M2Σ+(v = 0) with valence states B2Π(v = 22, 23) and L2Π(v = 3). Accurate energies for the M2Σ+ rotational levels are given. 相似文献
10.
Sorption of radionuclides on homogenized soils (under 2.5 mm grain size) from synthetic groundwater of 8·10−3M ionic strength and pH 8.5 has been studied under dynamic (flow) and static (batch) conditions. The corresponding water-soluble
compounds, as carriers in the 10−6 mol/dm3 concentration, were added into the SGW prior to the experiments. Soil samples were taken from several locations around the
environment of the High Level Waste Storage Facility at Nuclear Research Institute Řež plc in 5–100 cm depth. The dynamic
experiments were carried out in columns made of PP+PE injection syringes of 17.8 cm length and 2.1 cm in diameter. A multi-head
peristaltic pump was used for pumping the water upward through the columns at a seepage velocity of about 0.06 cm/min in average.
The radioactive nuclides were added into the water stream individually in a form of a short pulse in 0.1 cm3 of demineralized water. Dynamic desorption experiments were performed with the same experimental arrangement using a mixture
of 10−2N H2SO4 and 10−2N HNO3 in a volume ratio of 2: 1. Retardation, distribution and hydrodynamic dispersion coefficients during transport of radionuclides
were determined by the evaluation of the integral form of a simple advection-dispersion equation, used for fitting experimental
data and modeling the theoretical sorption breakthrough and desorption displacement curves. The static experiments were realized
in 100 cm3 plastic bottles stirring 5 g of soil samples with SGW occasionally in a soil to SGW ratio of 1: 10 (m/V). Kinetic parameters including equilibrium sorption activity, activity transfer rate constants and sorption half-times were
also determined. The results of dynamic experiments were compared with static sorption experiments. 相似文献
11.
V. L. Varand L. A. Glinskaya R. F. Klevtsova S. V. Larionov 《Journal of Structural Chemistry》2008,49(1):175-180
The [Y(Phen){(i-C4H9)2PS2}2NO3] mixed-ligand compound (I) was synthesized. Its structure was determined by X-ray diffraction analysis (X8 APEX diffractometer, λMoK
α
, 3788 F
hkl
, R = 0.0677). Crystals I are orthorhombic: a = 10.6495(8) Å, b = 20.006(2) Å, c = 35.317(4) Å, V = 7524.4(13) Å3, Z = 8, ρcalc = 1.324 g/cm3, space group Pbca. The structure is built of mononuclear discrete molecules. The N2O2S4 coordination polyhedron of the Y atom is a distorted dodecahedron.
Original Russian Text Copyright ? 2008 by V. L. Varand, L. A. Glinskaya, R. F. Klevtsova, and S. V. Larionov
__________
Translated from Zhurnal Strukturnoi Khimii, Vol. 49, No. 1, pp. 182–186, January–February, 2008. 相似文献
12.
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
13.
Near-infrared emissions of the b0+ → X10+, X21 band systems of TeSe have been observed in a discharge flow system. Analysis of the spectra yielded Te values of the X21 and b0+ states of 1235 ± 5 cm?1 and 8794 ± 5 cm?1, respectively, and a vibrational spacing in the b0+ state of ωe(b) = 294 ± 3 cm?1. 相似文献
14.
Lyudmila V. Chernykh Jitka Eysseltova Mikhail Y. Skripkin 《Monatshefte für Chemie / Chemical Monthly》2003,124(1):751-761
Solubility isotherms in the CuBr2−MBr−H2O (M
+ = Li+, Na+, Cs+) systems at 298.15 K were measured. The results together with other available literature data for copper chloride and bromide
systems were treated by hydration analysis, and comparative discussion of ionic processes taking place in the respective saturated
solutions was performed. 相似文献
15.
The potential energy curves for the X1∑ g, B1△g and B′1∑ g states of C2 have been studied by using MRCI and approximate CI methods, and are benchmarked against the calculations of full configuration interaction (FCI). The results obtained by MRCI method agree with the FCI very well, and even are accurate enough to compare other approximate methods as benchmark, when the calculations of FCI are not feasible. The approximate CI methods mentioned in this paper are reliable for treating chemical problems. 相似文献
16.
Lyudmila V. Chernykh Jitka Eysseltova Mikhail Y. Skripkin 《Monatshefte für Chemie / Chemical Monthly》2003,134(5):751-761
Summary. Solubility isotherms in the CuBr2−MBr−H2O (M
+ = Li+, Na+, Cs+) systems at 298.15 K were measured. The results together with other available literature data for copper chloride and bromide
systems were treated by hydration analysis, and comparative discussion of ionic processes taking place in the respective saturated
solutions was performed.
Corresponding author. E-mail: jitka@prfdec.natur.cuni.cz
Received August 6, 2002; accepted (revised) November 29, 2002
Published online April 3, 2003 相似文献
17.
V. A. Afanasieva L. A. Glinskaya R. F. Klevtsova I. V. Mironov 《Journal of Structural Chemistry》2005,46(5):876-882
Protonation equilibrium has been studied for the acyclic gold(III) tetraaza metallocomplex [AuB]2+ [B = N, N′-bis(2-aminoethyl)-2,4-pentanediiminato(1−)] in aqueous solution. The synthetic procedure is described. The crystal
and molecular structure of the protonated form of the [AuHB](H5O2)(ClO4)4 complex has been determined. Monoclinic crystals with unit cell dimensions a = 11.964(2) Å, b = 13.789(3) Å, c = 15.496(3) Å, β = 109.00(3)°, V = 2417.1(8) Å3, Z = 4, ρcalc = 2.243 g/cm3, space group P21/n. The structure is built of nearly planar [Au(C9H20N4)]3+ complex cations, (H5O2)+ cations, and [ClO4]− anions. The gold atom coordinates four nitrogen atoms of the ligand, forming a square plane. The six-membered chelate ring
of the ligand is protonated at the central β-carbon atom and contains imine C=N bonds. The oxygen atoms of the perchlorate
ions are hydrogen bonded to the (H5O2)+ dihydroxonium ion and to the nitrogen atoms of the NH2 groups of the [AuHB]3+ cation.
Original Russian Text Copyright ? 2005 by V. A. Afanasieva, L. A. Glinskaya, R. F. Klevtsova, and I. V. Mironov
__________
Translated from Zhurnal Strukturnoi Khimii, Vol. 46, No. 5, pp. 909–915, September–October, 2005. 相似文献
18.
The crystal structures of the Rh[(EtO)2PS2]3 (I) and Co[(PhO)2PS2]3 (II) chelate compounds were determined from X-ray diffraction (XRD) data (CAD-4 diffractometer, MoK
β radiation, 1193 F
hkl
, R = 0.0516 for I and 513 F
hkl
, R = 0.0305 for II). Crystals I are monoclinic: a = 14.233(3) Å, b = 13.570(3) Å, c = 14.272(3) Å; β = 90.66(3)°, V = 2756.3(10) Å3, Z = 4, ρcalc = 1.587 g/cm3, space group C2/c. Crystals II are trigonal: a = 15.149(2) Å, c = 30.306(6) Å; V = 6023.2(16) Å3, Z = 6, ρcalc = 1.493 g/cm3, space group R3ˉ. Structures I and II consist of discrete mononuclear molecules. The coordination polyhedra of the M atoms (M = Rh, Co)
are distorted octahedra formed by six sulfur atoms of three cyclic bidentate (RO)2 PS2− ligands.
Original Russian Text Copyright ? 2008 by R. F. Klevtsova, L. A. Glinskaya, and S. V. Larionov
__________
Translated from Zhurnal Strukturnoi Khimii, Vol. 49, No. 2, pp. 330–334, March–April, 2008. 相似文献
19.
The vibrational analysis of the CN(B2Σ+ → X2Σ+) emission sensitized by Hg(63P0) metastables has shown that the energy transfer process, Hg(63P0) + CN(X2Σ+) → Hg(61S0) + CN(B2Σ+), populates the CN(B2Σ+) state in a non-Franck-Condon fashion. The relative vibrational populations for the ν = 0 to 4 states are 1.00, 0.56 ± 0.06, 0.26 ± 0.03, 0.11 ± 0.03 and 0.04 ± 0.01, respectively. Long-range attractive interaction between the Hg(63P0) atom and the CN(X2Σ+) radical is evidenced by the observed high rotational excitation of the CN(B2Σ+) radical following the energy transfer process. 相似文献
20.
The field constant of the NQR frequency of a chlorine atom (35Cl) in a series of arsenic derivatives [R1R2R3AsCl]+M− was estimated from correlations. The field frequency is ∼41.5±3.5 Hz cm kV−1, which is nearly twice as much as that in analogous phosphorus compounds.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1758–1760, August, 2005. 相似文献