The article reviews the history of studies of Koguryo culture ceramics that has been largely neglected in the Russian historical scholarship. While completing the Master's course in archeology at the Koryo University (Korea) in 2005-2009 the author had an opportunity to examine the collections of ceramic vessels excavated from archaeological sites of Koguryo culture: Hon Rengbon 1-2, Achasan 4, Gueoidong, Shirubong, Horogoru, Engmasan-1-3. Having analyzed the collected data and published materials the author described the basic types of ceramic vessels and determined basic attributes of Koguryo ceramics.
The article examines the history of archaeological research of the Heishui Mohe sites (the Naifeld group of the Mohe archaeological culture) in the Еastern part of Asia. The article highlights the main stages of cultural studies, reviews the major works on this issue.
The article shows the current stage of research of the pre-Colombian cultures of Central America in Russian archaeological literature. This region has never been studied by Russian scholars in the course of expeditions or special research projects. The available information is quite sketchy and out of date.
The aim of the article is to study the iron shoe tips dated from the XVII century and found in the cultural layer of Tobolsk. These findings let partially characterize blacksmith and shoemaker work in Siberia's old capital. Analysis of scientific literature allows determining some problems related to classification and chronology of shoe tips in the Moscow state and neighbouring areas. The author carried out the statistical analysis, developed classification of the Tobolsk findings and studied several published collections. All this allowed him to conclude that problems of chronology and classification of shoe tips should be studied individually for each archaeological record.
The article deals with development of the housing and settlement complex of the Buryats of the Eastern Sayan area in the second half of the XIX - the beginning of the XX centuries. Based on the analysis of historical sources the author demonstrates that during that period of history the number of settlements increased, there appeared new forms of settlements and novelties in architecture of log yurtas, along with adoption of the Russian-Siberian type of dwellings which resulted in constructing the new hybrid types of houses.
The article concerns religious objects and buildings of the Festival of Ysyakh focusing on the problem of spiritual development of space, correlation between ritual objects and mythological worldview. Based on various sources, the article considers symbolical and functional significance of Yasyakh' buildings.
The author undertakes examination of peasant autobiographies in order to analyze patterns their perception of the natural environment. Peasant handwritten autobiographies explore views and opinions of the rural population through the period of modernization in Siberia in the XIX and XX centuries. They also show transformation of these traditional views from considering the nature a source of material wealth to acknowledging exhaustibility of its resources.
G.N. Varavina
Keywords: indigenous numerically small peoples of the North, Tungus-speaking ethnic groups, spiritual culture, conceptions of soul, semantics of thread and hair
Pages: 93-100
The article provides a valuable overview of the traditional concepts of human nature shared by the Tungus-speaking ethnic groups (Evens and Evenks). The author reviews evidence gained from ethnographic and folklore research findings in an effort to describe traditional concepts of soul and relevant ritual practices.
The authors study a traditional Khakass women's breast adornment (pogo), its semantics, symbolism and place in the structure of cultural and historical heritage of the Khakass Republic. The authors conclude that pogo has become a part of heraldic art and symbolizes the polyethnic Khakass society.
The article studies the forms of visiting in the traditional and modern Kazakh culture. The research is based on concepts and practices of conspicuous consumption and gift exchange. The authors argue that the norms and standards of visiting, which remained steady for centuries, are a form of social reproduction both from socioeconomic and mythical-ritual perspectives.
The paper evaluates the Republic of Korea's strategy for interacting with Korean diaspora communities. The author defines diaspora as an institutionalized community of immigrants with high level of integration into the receiving society and collective memory of the historical homeland; offers general and specific characteristics of the most numerous groups of the Korean diaspora. The novelty of research is determined by the original sources allowing to trace evolution of the Republic of Korea's policy towards diaspora.
The article concerns the image of crane in mythological and ritual system of the Khakasses. Based on the literature, archival and field materials, the author considers the connection of this bird with concepts of man's soul and death. The author also analyzes the links of the image of crane and its nest with concepts of home and womanliness.
In the XVII century the grown-up sons of the Siberian Cossacks formed a special social group. In cases of emergency they served as a potential military force for Siberian garrisons. Some of the Cossacks' sons took the positions of their fathers or other kins in case of the latter's resignation or death. But the large majority of the Cossacks' sons were engaged in farming and trade. Gradually they dissolved among the other social groups, joining the ranks of peasants and small commodity producers.
This article studies activities of a special committee authorized to transfer the property of the Trans-Baikal Cossack Army to the relevant organizations of the Far Eastern Republic in 1920-1921. The author shows the committee's role in liquidation of the Cossack self-government bodies; analyzes its formal and actual place in the administrative system; demonstrates problems of its interaction with the local and central authorities.
The paper considers the main trends in development of subsistence farms of industrial enterprises and organizations in Western Siberia. The author concludes that subsidiary plots appeared as a result of inconsistent policy of the Soviet government attempting to solve the problem of food shortage in this period of history.
Y. N. Zhuravlev, I. A. Fedorov, M. Y. Kiyamov
Keywords: naphthaline, anthracene, crystal structure, pressure, equation of state, bulk modulus, Gr?neisen parameter
Pages: 425-431
A first - principles method of density functional theory with a gradient approximation of the exchange-correlation potential in the form of PBE implemented in the PWscf program of the Quantum ESPRESSO software using the Grimme′06 scheme is used to calculate the crystal structure of naphthaline and anthracene at a hydrostatic pressure ranging from 0 GPa to 2 GPa and from 0 GPa to 20 GPa respectively; their equations of states are analyzed. It is shown that under pressure the volume decreases due to voids, and the molecules themselves are practically not deformed. The Grüneisen parameter is calculated in the Slater-Dugdale-MacDonald-Zubarev-Vashchenko model. This parameter decreases from the equilibrium values of 2.356 (anthracene) and 3.226 (naphthaline) with an increase in the pressure. With the use of the Mie-Grüneisen equation under the additional Hugoniot-Renkin condition the impact pressure is calculated, which increases compared to the cold one at a relative compression V/V0, below 0.7.
A method to solve the problem of the electron-nuclear states of molecules with internal rotation and the smeared positions of nuclei due to this rotation is proposed. It is shown how to state the Hamiltonian for the description of the electron motion with regard to this smearing and the total electron-nuclear Hamiltonian.
G. V. Baryshnikov, B. F. Minaev, V. A. Minaeva, A. T. Baryshnikova
Keywords: density functional theory, Bader's method, geometric isomers, hydrogen bond
Pages: 436-442
At the DFT level with the B3LYP hybride functional the structure and relative stability of geometric isomers of bi- and trithiazolidine-4-ones are calculated. Based on Bader's analysis of the electron density distribution the presence of intramolecular hydrogen bonds and van der Waals interactions is found in the studied isomers. Energies of these interactions are calculated. It is shown that the presence of a substituent in the thiazolidine ring affects the stabiliyty of the studied geometric isomers.
M. Juh??sz1, S. Takahashi1, S. Arulmozhiraja2, T. Fujii1 1 Department of Chemistry, Faculty of Sciences and Engineering, Meisei University 2 Research School of Chemistry, Australian National University fujii@chem.meisei-u.ac.jp
Keywords: cis-diamminedichloroplatinum(II), bond strength, cation affinities, B3LYP density functional
Pages: 443-448
The energies of the Pt-NH3 and Pt-Cl bonds of cisplatin are calculated by means of a density functional theory method with the B3LYP functional and various basis sets. The calculated bond energies of 37.38 kcal·mol-1 and 64.35 kcal·mol-1 for Pt-NH3 and Pt-Cl, respectively, agree well with the experimental values (37.28 kcal·mol-1 and 69.31 kcal·mol-1 respectively) derived from enthalpy changes. The proton and lithium ion affinities of cisplatin are also obtained with the B3LYP functional. Structural characterizations for the protonated and lithiated cisplatin complexes are given. Protonation and lithiation alter the geometric parameters, and the gas-phase proton affinity (198.71 kcal·mol-1) is much higher than the lithium ion affinity (70.32 kcal·mol-1).
X.L. Yu1, Z.D. Tan2, X.Y. Wang3 1 College of Chemistry and Chemical Engineering, Hunan Institute of Engineering Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry 2 College of Chemistry and Chemical Engineering, Hunan Institute of Engineering 3 Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry
Keywords: artificial neural network, density functional theory, monomer, radical copolymerization, QSPR, quantum chemical descriptors
Pages: 449-544
To construct artificial neural network (ANN) models for the prediction of reactivity parameters (u, v), density functional theory (DFT) calculations are carried out for 55 vinyl monomers, at the B3LYP level of theory with a 6-31G(d) basis set. After the generation of quantum chemical descriptors, the stepwise multiple linear regression (MLR) analysis and the ANN method are used to develop quantitative structure-property relationship (QSPR) models of parameters u and v. The ANN models produced test set root-mean-square (rms) errors of 0.35 for the parameter u and 0.34 for the parameter v. Research results indicate that the QSPR models based on DFT calculations and ANN techniques are accurate and possess the ability to generalize.
Methods to measure the bond rupture force are considered. It is proposed to use a quartz resonator as an active element rather than simply a sensor. When the surface oscillation amplitude of an AT quartz resonator increases smoothly (rupture event scanning), a particle attached to the quartz surface is removed by inertial forces, and from their values it is easy to obtain the bond dissociation value. This procedure provides reliable measurements of the rupture force of about 10 pN. As the atomic force microscopy method, the rupture event scanning does not apply electromagnetic radiation, but has simpler instrumental set-up. The scanning requires minimum sample preparation, can be performed in various media (vacuum, air, liquid), and takes only a few minutes.
S.A. Beyramabadi1, A. Morsali1, S.H. Vahidi1, M.J. Khoshkholgh2, A.A. Esmaeili2 1 Department of Chemistry, Mashhad Branch, Islamic Azad University 2 Department of Chemistry, Faculty of Science, Birjand University beiramabadi@yahoo.com
Keywords: DFT, IR assignment, NMR, Schiff base, salen, copper(II)
Pages: 466-473
A new tetradentate N,N′-dipyridoxyl(1,2-ethylenediamine) [=H2ES] Schiff-base ligand and its Cu(II) salen complex [Cu(ES)(H2O)] are synthesized and characterized by IR, UV-Vis, 1H NMR, mass spectrometry, and elemental analysis. Their optimized geometries and theoretical vibrational frequencies are computed by using the density functional theory method where the B3LYP functional was used. Also, the 1H NMR chemical shifts of the H2ES ligand are calculated at the same computational level. In the optimized structure of the free ligand, two pyridine rings are not in the same plane. In the structure of the complex, the Schiff-base ligand acts as a dianionic tetradentate ligand in the N,N,O-,O- manner, so that the coordinating atoms occupy equatorial positions. The H2O ligand occupies the axial position of the square-pyramidal complex. The calculated results are consistent with the experimental ones, confirming the suitability of the optimized structures for the H2ES ligand and its Cu(II) complex.
N. É. Dubinin, A. A. Yuryev, N. A. Vatolin
Keywords: liquid metal, reference system, pseudopotential, pair interatomic interaction, variational method, structure factor, thermodynamic properties
Pages: 474-481
We investigate the applicability of a variational method with a new reference system (square-well model) to the description of the structure and thermodynamics of liquid metals. An expression for the system entropy for a one-component fluid is derived. The three parameters of the model (the hard-sphere diameter and the width and depth of the square well) are determined by the variational method using the local pseudopotential approximation. The approach is used for liquid Na and K, and the calculated results are compared with experiment. It is shown that the approach can provide a realistic description of the properties of liquid metals.
The Monte Carlo method is used to simulate similar sized hard sphere systems in a wide range of densities (from η 0.005 to 0.530 with a step of η = 0.005). The models are used to calculate the coefficients of the thermodynamic perturbation theory series for SW fluids up to the fourth order. The width of the attraction zone of the SW potential λ is varied from 1 to 2.5 sphere diameters. The analytical expressions approximating the obtained coefficients by polynomials with respect to the variables η and λ are determined. The absolute accuracy of the approximation is estimated to be better than ±0.001. All the necessary data for the calculation of the Helmholtz free energy of SW fluids up to the fourth-order perturbation theory are given.
V. K. Abrosimov, E. Y. Lebedeva
Keywords: helium, water, aqueous solutions of sodium chloride, solubility, temperature and pressure effects, Sechenov parameters, pairwise interaction parameters
Pages: 492-500
The data on the solubility of helium in water and aqueous solutions of sodium chloride at a temperature of T = 293-353 K and a He partial pressure of p2 = 0.1-20 MPa are used to calculate the standard parameters of the Sechenov salt effect and estimate, within the formalism of the McMillan-Mayer theory, the parameters of the pairwise solute-solute interaction.
E. G. Tarakanova, G. V. Yukhnevich
Keywords: binary liquid system, IR spectrum, quantum chemical calculation, hydrogen bond, heteroassociates, hydrogen fluoride, acetone
Pages: 501-507
The vibrational spectra of a series of HF solutions in acetone (1:20-8.9:1) are analyzed with the help of special techniques. It is shown that three types of strong heteroassociates (HAs) with 1:1, 4:1, and ≥10:1 stoichiometric ratios of the molecules are formed in the HF-(CH3)2CO binary liquid system. The concentration ranges of the existence of HAs in the solution and the stretching vibrational frequency of their constituent HF molecules are estimated. The density functional method (B3LYP/6-31++G(d,p)) is used to calculate the optimal configurations and IR spectra of the (HF)m·((CH3)2CO)n molecular complexes (m = 1, 2, 4, 8, n = 1, 2) of different structure. The relative stability of the latter is studied. By comparing the calculated and experimental data, the composition (2:2 and 4:1) and structure of two types of HAs are determined.
A. I. Gubanov, N. V. Kuratieva, E. Y. Filatov, S. V. Korenev
Keywords: rhodium, cobalt, complex salt, single crystal, powder X-ray diffraction study, coordination ion stabilization
Pages: 508-514
The structures of two salts [Co(NH3)6][Rh(NO2)6] (I) and [Co(NH3)6][(NO2)3Rh(μ-NO2)1+x(μ-OH)2-x Rh(NO2)3]·(2-x)(H2O), x = 0.17 (II) are solved. Single crystals of the salts are obtained by the counter diffusion method through the gel of aqueous solutions of [Co(NH3)6]Cl3 and Na3[Rh(NO2)6]. The structure of [Co(NH3)6][Rh(NO2)6] is consistent with the diffraction data for a polycrystalline sample of poorly soluble fine salt formed in the exchange reaction between aqueous solutions of [Co(NH3)6]Cl3 and Na3[Rh(NO2)6]. The structure of [Co(NH3)6][(NO2)3Rh(μ-NO2)1+x(μ-OH)2-xRh(NO2)3]·(2-x)(H2O), x = 0.17 exhibits the stabilizing effect of a large cation in the formation of novel, unknown previously coordination ions: [(NO2)3Rh(μ-NO2)(μ-OH)2Rh(NO2)3]3- and [(NO2)3Rh(μ-NO2)2(μ-OH)Rh(NO2)3]3-.
A novel copper(II) complex {[Cu(BIX)2(H2O)2](PhCOO)2}n (1) (BIX = 1,4-bis(imidazole-1-methyl))benzene) is synthesized and characterized by elemental analysis, IR, TG, and single crystal X-ray diffraction. Complex 1 crystallizes in the triclinic crystal system with the P-1 space group, Z = 1, a = 9.465(2) Å, b = 9.703(2) Å, c = 12.060(2) Å, α = 77.26(3), β = 70.37(3), γ = 67.14(3)°, and V = 956.1(3) Å3. The crystal structural analysis of complex 1 shows that the copper center is six-coordinated in an elongated octahedral geometry by four N atoms from four different BIX and two O atoms from two water molecules; two neighboring Cu(II) cations are bridged by two BIX extending into an infinite 1D double chain structure.
S. P. Khranenko, E. A. Bykova, A. V. Alexeyev, S. A. Gromilov
Keywords: palladium, rhenium, ethylenediamine, nitrate, crystal chemistry, single crystal X-ray diffraction study
Pages: 520-526
At T = 150 K, the crystal structures of [Pd(En)2](ReO4)2, [Pd(En)2](NO3)2, and [PdL2](ReO4)2 (L is N,N′-diisopropylideneethane-1,2-diamine) are studied. Crystal chemical analysis is performed, and the main factors affecting the packing of fragments in these structures are determined.
S. P. Khranenko, E. A. Bykova, A. V. Alexeyev, A. P. Tyutyunnik, S. A. Gromilov
Keywords: rhodium, rhenium, molybdenum, tungsten, complex salt, crystal chemistry, single crystal X-ray diffraction study
Pages: 527-533
Four complex salts with the polyatomic [Rh(NH3)6]3+ cation are synthesized and studied by X-ray diffraction. The crystallographic characteristics of [Rh(NH3)6](WO4)Cl are determined and the structures of [Rh(NH3)6]Cl3, [Rh(NH3)6](ReO4)3·2H2O, and [Rh(NH3)6](MoO4)Cl·3H2O are solved. The features of mutual packing of the fragments are studied.
A. A. Rybinskaya, P. E. Plyusnin, E. A. Bykova, S. A. Gromilov, Y. V. Shubin, S. V. Korenev
Keywords: rhodium, palladium, double complex salts, single crystal X-ray diffraction study, thermal analysis, nanoalloy
Pages: 534-539
Two new double complex salts [Pd(NH3)4]3[Rh(NO2)6]2 (I) and [Pd(NH3)4]3[Rh(NO2)6]2·H2O (II) are synthesized and characterized. The techniques to produce one-phase residues of the salts are developed. The crystallographic data for I: a = 18.915(2) Å, V = 6767.4 Å3, F-43c space group, Z = 8, dx = 2.548g/cm3; II: a = 21.160(6) Å, b = 8.085(7) Å, c = 21.363(4) Å, β = 91.71(4)°, V = 3661.1(6) Å3, P21/c space group, dx = 2.357 g/cm3. Thermal properties of the obtained compounds in the hydrogen and helium atmosphere are studied. It is shown that the final product of their decomposition both in the inert and reducing atmosphere is a powder consisting of bimetallic nanosized particles (nanoalloy) of Pd0.59Rh0.41 (Fm-3m space group, a = 3.856(2) Å, crystallite size of 8-11 nm).
H.X. Ma1, N.N. Zhao1, B. Yan2, Y.L. Guan1, J.F. Li1, J.R. Song3 1 College of Chemical Engineering, Shaanxi Key Laboratory of Physico-Inorganic Chemistry, Northwest Univer- sity 2 College of Chemical Engineering, Shaanxi Key Laboratory of Physico-Inorganic Chemistry, Northwest Univer- sity School of Chemistry and Chemical Engineering, Yulin University 3 College of Chemical Engineering, Shaanxi Key Laboratory of Physico-Inorganic Chemistry, Northwest Univer- sity Conservation Technology Department, the Palace Museum mahx@nwu.edu.cn
Keywords: bis-(3, 3-dinitroazetidinyl)-oxamide ((DNAZ-CO)2), molecular structure, quantum chemical investigation, thermal behavior
Pages: 540-547
Bis-(3,3-dinitroazetidinyl)-oxamide ((DNAZ-CO)2) is an acyl derivative of 3,3-dinitroazetidine (DNAZ). It is prepared and its crystal structure is determined. The crystal is orthorhombic, Fdd2 space group, a = 13.136(14) Å, b = 19.48(3) Å, c = 10.326(14) Å, V = 2642 (6) Å3, Z = 8. A density functional theory (DFT) method of the Amsterdam Density Functional (ADF) package is used to calculate the geometry, frequencies, and properties. The optimized geometry, frontier orbital energy, and main atomic orbital percentage are obtained. The thermal behavior is studied under a non-isothermal condition by DSC and TG/DTG methods. The apparent activation energy (Ea) and pre-exponential factor(A) of the exothermic decomposition reaction of (DNAZ-CO)2 are 164.10 kJ·mol-1 and 1013.38 s-1 respectively. The critical temperature of thermal explosion is 272.20 °C. The values of ΔS≠, ΔH≠, and ΔG≠of this reaction are 6.44 J·mol-1··K-1, 163.76 kJ·mol-1 and 160.34 kJ·mol-1 respectively.
Single crystal XRD is used to study the crystals of salts of indole alkaloid norfluorocurarine: hydrochloride recrystallized from absolute alcohol, dihydrate hydrochloride recrystallized from water, methochloride monohydrate recrystallized from water, solvate form of methochloride obtained from ethanol, and methobromide monohydrate. Intra- and intermolecular hydrogen bonds are analyzed in these crystals. The crystal structures of norfluorocurarine methochloride and methobromide monohydrates are isomorphic. In norfluorocurarine salts, the orientation of the carbonyl group is determined by the intramolecular С19=О…H-N1 hydrogen bond that is absent in the solvate form with ethanol.
D. A. Yatsenko, V. P. Pakharukova, S. V. Tsybulya, A. A. Matvienko, A. A. Sidel'nikov
Keywords: powder X-ray diffraction, structural studies, modeling, iron oxides, nanopowders, Debye formula, radial distribution function
Pages: 554-562
X-ray diffraction studies of the ultradisperse products of the solid-phase oxidative thermolysis of iron oxalate dehydrate are performed. Models are considered and diffraction patterns are calculated for the nanopowders of different crystalline modifications of iron oxide. Calculations are performed for the particles of various shapes and sizes, starting from one unit cell. Despite that the final product is the hematite phase, the reaction is shown to pass through the formation of particles with the ferrihydrite structure.
E. A. Bykova, A. V. Zadesenets, T. V. D'yachkova, E. Y. Gerasimov, S. A. Gromilov
Keywords: rhenium, platinum, nanosized particles, complex salt, X-ray diffraction, crystal chemistry
Pages: 563-568
Alloys of the composition Re0.65Pt0.35 are prepared by thermal reduction of a bimetallic complex salt (NH4)2[ReCl6]0.65[PtCl6]0.35 in the hydrogen atmosphere and also by thermal-baric treatment of a mixture of nanosized powders of rhenium and platinum. The products are examined by powder X-ray diffraction and HRTEM. The compositions of the obtained phases are estimated using EDS and crystal chemical analysis of phases known for the Re-Pt system.
M. Y. Dolomatov, S. A. Shutkova, S. V. Dezortsev
Keywords: petroleum asphaltenes, nanoparticles, non-planar cup-like structure, asphaltene molecules
Pages: 569-573
Ab initio RHF/3-21G** and ММ+ molecular mechanics method are employed to calculate the structural chemical parameters of molecular nanoparticles of petroleum asphaltenes. It is found that naphtheno-aromatic rings have a non-planar cup-like character. The values of dihedral angles α1 between the planes of aromatic and naphthene rings, which are calculated by the RHF/3-21G** method, are within 156-163°. The values of dihedral angles α2, which were calculated by the molecular mechanics method, are within 156-164°.
T. M. Polyanskaya, A. I. Smolentsev
Keywords: pyrogallol, dimethylsulfoxide, structure, single crystal, molecular complex, intermolecular interaction, hydrogen bond
Pages: 574-579
The crystal structure is solved for a 1:1 molecular complex of pyrogallol and dimethylsulfoxide. Crystal dat a: C8H12O4S, M = 204.24, orthorhombic, Pna21 space group; unit cell parameters: a = 10.9620(4) Е, b = 10.9542(4) Е, c = 8.0561(3) Е, V = 967.38(6) Е3, Z = 4, dx = 1.402 g/cm3, R1 = 0.0216, T = 150 K. The molecules are joined in a supramolecular ensemble by O-HпO and C-HпА hydrogen bonds.
E. Mousavinezhad sarasia1, M.E.S. Soliman2, B. Honarparvar3 1 Department of Biochemistry, Payame Noor University 2 School of Pharmacy and Pharmacology, University of KwaZulu Natal 3 School of Chemistry, University of KwaZulu Natal Honarparvar@ukzn.ac.za bahareh_honarparvar@yahoo.com
Keywords: salicylamide (SAM), gentisamide (GAM), HOMO-LUMO band gap, excitation energies, ab initio
Pages: 580-587
A systematic computational study was carried out to determine the structural stability of salicylic acid derivatives as well as the acidic properties of the protonation-deprotonation site and excitation parameters of the considered drugs at different temperatures using quantum chemical calculations. For further structural information, the dipole moment and differences in the energy of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) as Δ(HOMO-LUMO) were compared. A high stability of the salicylic acid derivatives was referred to the large HOMO-LUMO band gap. The result of the current study may give useful information about the drug biochemical functionality based on the physical and chemical nature at different temperatures, and in this way the study on the structural features of analogous molecules of salicylic acid derivatives with higher drug functionality would be possible.
C. Buend??a-atencio
INIFTA, Facultad de Ciencias Exactas, Universidad Nacional de La Plata Grupo de Química Cuántica y Teórica, Facultad de Ciencias Exactas y Naturales, Universidad de Cartagena cbuendia92@inifta.unlp.edu.ar
Keywords: halotrifluoromethylsulfane, quantum chemistry, ab initio calculations, geometric structure, enthalpies of formation
Pages: 588-592
Enthalpies of formation ((g)) are calculated for syn and anti conformers of FC(O)SCF3 and ClC(O)SCF3 using the atomization methods with the Gaussian-n composite methods for which experimental values do not exist. DFT approaches and MP2 methods are employed to optimize the molecular geometries of XC(O)SCF3 (X = F and Cl). Excellent results are obtained with the reported experimental data.
N. V. Pervukhina, S. V. Borisov, S. A. Magarill, N. V. Kuratieva, N. N. Mozgova, I. V. Chaplygin
Keywords: heyrovskyite, Pb-Bi sulfosalts, tablet structures, isomorphism Pb/Bi, crystal structure
Pages: 593-597
Heyrovskyite mineral Pb6Bi2S9 from fumarole exhalations of the Kudryavyi volcano (Iturup island, Kurils, Russia) is studied by X-ray crystallography (Bruker Nonius X8 Apex with a 4K CCD detector, R = 0.0405). Unit cell parameters are: a = 4.1457(1) Å, b = 13.7421(5) Å, c = 31.5005(12) Å, V = 1794.6(1) Å3, Z = 4, dx = 7.216 g/cm3, Cmcm space group, R=0.0405. The resulted structure is similar to the known structures of heyrovskyites from other deposits with some variation in the cation composition.
