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2013 year, number 2
A. V. Luzanov
Institute for Single Crystals, National Academy of Sciences of Ukraine, Kharkiv luzanov@xray.isc.kharkov.com
Keywords: diamagnetism, paramagnetism, π electron correlation, number of effectively unpaired electrons, aromaticity
Abstract >>
The previously developed scheme of the full configuration interaction for magnetic perturbations of π systems is transformed into a scheme for calculations in the finite field. It helps create “magnetic portraits” of molecules, reflecting the essentially non-linear behavior of conjugated systems in a strong field. In particular, possible latent paramagnetism of aromatic systems and correspondingly latent diamagnetism of antiaromatic ones is easily detected. The degree of the π electron shell openness as well as the singlet-triplet splitting in the field are evaluated. From the data obtained it follows that in the strong magnetic field an aromatic molecule becomes as a rule biradicaloid and non-aromatic. Accordingly, an antiaromatic system dramatically reduces its initial biradicaloid character and thus loses its antiaromaticity.
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T. Hosseinnejad1, S.J. Ahmadi2, M.H. Karimi-Jafari3
1Department of Chemistry, Faculty of Science, Alzahra University, Vanak, Tehran, Iran tayebeh.hosseinnejad@gmail.com 2Nuclear Science and Technology Research Institute (NSTRI), Tehran, Iran 3Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
Keywords: ion imprinting, lanthanide complexes, density functional theory, polarized continuum model, conformational distribution
Abstract >>
In the present research, we have mainly concentrated on the survey of interactions in Ln3+ (Ln = La, Ce, Nd and Sm) ternary complexes of 5,7-dichloroquinoline-8-ol (DCQ) and 4-vinyl pyridine (VP), [Ln(VP)2(DCQ)3]3+ by means of density functional theory, Hartree-Fock and Sparkle/PM3 semi-empirical computational methods. For VP and DCQ ligands, the cation binding energy sequence follows the order La3+ > Ce3+ > Nd3+ > Sm3+ as expected based on increasing in the hardness and decreasing in the ionic radius of this lanthanide cation series. A similar trend was observed in the calculated binding energy of the aforesaid ligands with the hydrated lanthanide cation series [Ln(H2O)9]3+, while the computed values of deformation energy of ligands upon complexation demonstrated an opposite order in the lanthanide cation series. Moreover, the solvent effects are considered via a polarized continuum model and provided a significant increase in the binding strength while the relative magnitude of binding energies is the same as that in the gas phase. Combining quantum and statistical mechanical calculations, we have also determined quantitatively a reliable estimate of the conformational distribution of the [Sm(VP)2(DCQ)3]3+ complex at various temperatures in the gas phase by computing the molecular partition functions and consequently the analysis of the conformational equilibrium constants.
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J.X. Liang1, Y.B. Wang1, Z.Y. Geng2,3, Y.Z. Wang2,3, Y.C. Wang2,3
1College of Chemical Engineering, Northwest University for Nationalities, Lanzhou, Gansu, P. R. China wangyb16@yahoo.cn 2Gansu Key Laboratory of Polymer Materials, College of Chemistry and Chemical Engineering, Key Laboratory of Eco-environment-related Polymer Materials 3Ministry of Education, Northwest Normal University, Lanzhou, Gansu, P. R. China
Keywords: isobutenyl anion, reaction mechanism, second-order Moller—Plesset perturbation theory (MP2)
Abstract >>
Calculations using conventional ab initio theory are performed to investigate the reaction mechanism associated with the gas-phase ion/molecule reaction of isobutenyl anion with N2O. As a result, our theoretical findings strongly suggest that the main pathway is the reaction pattern of end-N attack and that the corresponding reaction mechanism basically relates to hydrogen migration, which may yield products cis-CH2(CH3)CCN–2, trans-CH2(CH3)CCN–2, and H2O. Those are in good agreement with the experimental observations. Moreover, based on the NBO, Activation Strain model and methyl group effect analysis, we also explored the characters of rate-determining step of the main pathway.
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A.Y. Musa1, W. Ahmoda1, A.A. Al-Amiery2, A.A.H. Kadhum1, A.B. Mohamad1
1Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment, University Kebangsaan Malaysia, Bangi, Selangor, Malaysia 2Biotechnology Division, Applied Science Department, University of Technology, Baghdad, Iraq dr.ahmed@eng.ukm.my; dr.ahmed1975@gmail.com
Keywords: corrosion inhibition, quantum chemical parameter, thio, QSAR
Abstract >>
The effects of the molecular structure on the corrosion inhibition efficiency are investigated by nine methods of calculations. The selected thio compounds were previously identified as corrosion inhibitors for mild steel in the 1.0 M HCl solution. The electronic properties such as highest occupied molecular orbital (EHOMO) energy, lowest unoccupied molecular orbital (ELUMO) energy, dipole moment (μ), and Fukui indices are calculated and discussed. Results show that the corrosion inhibition efficiency increase with the increase in both EHOMO and m values, respectively, and decrease in ELUMO. QSAR approach is utilized in this study; a good relationship is found between the experimental corrosion inhibition efficiency (IEExp%) and the theoretical corrosion inhibition efficiency (IETheo%). The calculated inhibition efficiency is found closer to the experimental inhibition efficiency with a coefficient of correlation (R2) of 0.875.
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L. A. Gribov, B. K. Novosadov
V. I. Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Moscow l_gribov@mail.ru
Keywords: Schrodinger equation, Hamiltonian of the molecule, quantum chemistry, numerical solution
Abstract >>
The numerical solution algorithm of the Schrödinger equation proposed in [1-5] is described, in which the electron-nucleus interaction operator has an integral representation over the nuclear distribution, and the equation itself is written in separable variables of electrons and nuclei.
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A. N. Kozachkova1, N. V. Tsaryk1, A. V. Dudko1, V. I. Pekhnyo1, V. M. Novotortsev2, I. L. Eremenko2, V. V. Minin2, N. N. Efimov2, E. A. Ugolkova2
1V. I. Vernadsky Institute of General and Inorganic Chemistry, National Academy of Sciences of Ukraine, Kiev complex@ionc.kiev.ua 2N. S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Moscow
Keywords: heterometallic complex of Pd(II) and Cu(II), aminodiphosphonate, single crystal X-ray analysis, magnetic properties
Abstract >>
A heterometallic complex of Pd(II)–Cu(II) with 1-aminoethylidene-1,1-diphosphonic (AEDP) acid (C4H22CuN2O16P4Pd)n (²) is synthesized. Single crystals of compound ² are obtained; its crystal structure is determined by X-ray crystallography. The crystals are orthorhombic, space group Pbcn , a = 18.366(3) Å, b = 9.7661(17) Å, c = 20.198(4) Å, V = 3622.8(11) Å3, Z = 8, dx = 2.376 g/cm3. The compound crystallizes as a coordination polymer; the square environment of Pd(II) is formed by nitrogen atoms of amino groups and oxygen atoms of phosphonic groups, while at two non-equivalent copper atoms the octahedral environment is formed by oxygen atoms of phosphonic groups and water molecules. The crystal structure of compound I is characterized by the formation of a branched network of hydrogen bonds. Based on the analysis of the temperature dependence of the magnetic susceptibility it is found that for the heterometallic complex of Pd(II)–Cu(II) with AEDP antiferromagnetic interactions between the paramagnetic centers are dominant.
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M. Karakaya, F. Ucun
Department of Physics, Faculty of Arts and Sciences, Süleyman Demirel University, Isparta Turkey mkarakayafizik@hotmail.com
Keywords: acetylcholine halide, vibration, DFT, IR, Raman, NMR
Abstract >>
The optimized molecular structures, vibrational frequencies and 1H and 13C NMR chemical shifts of acetylcholine halides (F, Cl and Br) have been investigated using density functional theory (B3LYP) method with 6-311G( d) basis set. The comparison of their experimental and calculated IR, R and NMR spectra of the compounds has indicated that the spectra of three optimized minimum energy conformers can simultaneously exist in one experimental spectrum. Thus, it was concluded that the compounds simultaneously exist in three conformations in the ground state. The calculated optimized geometric parameters (bond lengths and bond angles), vibrational frequencies and NMR chemical shifts for the minimum energy conformers were seen to be in a good agreement with the corresponding experimental data. All the assignments of the theoretical frequencies were performed by potential energy distributions using VEDA 4 program.
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A. S. Roik1, A. V. Anikeenko2, N. N. Medvedev2,3
1Chemistry Department, National Taras Shevchenko University of Kyiv, Kyiv, Ukraine sasha78@univ.kiev.ua 2Institute of Chemical Kinetics and Combustion, Siberian Division, Russian Academy of Sciences, Novosibirsk, Russia 3Novosibirsk State University, Novosibirsk, Russia
Keywords: metallic melts, single-crystal X-ray diffraction analysis, prepeak, icosahedral short-range order, chemical short-range order, polytetrahedral clusters
Abstract >>
The reasons are investigated for the prepeak and the asymmetry of the second peak in the structure factor curve that are observed in a variety of metallic melts. The prepeak is observed as an additional maximum in the left wing of the main peak of the structure factor for multicomponent melts and is attributed to their chemical short-range order (CSRO). The asymmetry of the second peak in the structure factor, which is usually explained by the “icosahedral” (polytetrahedral) order in the melt, is observed both for multicomponent systems and for pure metals. However, some aluminum alloys with transition metals exhibit the two features simultaneously, which requires an explanation. An X-ray diffraction study of the liquid ternary Al66.6Mn16.7Co16.7 alloy is performed at 1393 K and that of liquid copper at 1353 K, 1403 K, and 1553 K. The reverse Monte Carlo (RMC) method is used to derive structural models of these and other melts. Structural analysis of these melts is conducted using Delaunay simplices. A theoretical simulation of CSRO is performed in the model of liquid aluminum, the structure factor of which does not have these features. It is discussed that CSRO can exist in a melt regardless of the presence of the polytetrahedral order.
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V. N. Afanas’ev, A. N. Ustinov
G. A. Krestov Institute of Solution Chemistry, Russian Academy of Sciences, Ivanovo vna@isc-ras.ru
Keywords: conventional compressibility of hydrated complexes, conventional compressibility of the free solvent, hydration
Abstract >>
We use our own and literature data on density, ultrasound propagation velocity, and isobaric heat capacity to study the concentration, temperature, and pressure dependences of solvation numbers in aqueous NaCl solutions. We show that, in the parameter range: m = 0-6.0 mol×kg –1, p = 1-1000 bar, and T = 283.15-323.15 K, the solvation numbers decrease with increasing concentration, pressure, and temperature.
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O. N. Kazheva1, D. A. Rudakov2, G. V. Shilov1, O. A. D’yachenko1, V. I. Potkin2
1Institute of Problems of Chemical Physic, Russian Academy of Sciences, Chernogolovka, Russia deach@list.ru 2Institute of Physical Organic Chemistry, National Academy of Sciences of Belarus, Minsk, Belarus
Keywords: halogenation, dicarba-nido-undecaborate, single-crystal X-ray diffraction analysis, nuclear magnetic resonance
Abstract >>
A technique is proposed for directed synthesis of 6,11-dichloro-9-dimethylthio-7,8-dicarba- nido-undecaborane [6,11-Cl2-9-SMe2-7,8-Ñ2Â9Í9]. Single-crystal X-ray diffraction is used to identify the molecular and crystal structure of the compound.
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S. B. Aliev1, D. G. Samsonenko1,2, V. P. Fedin1,2
1A. V. Nikolaev Institute of Inorganic Chemistry, Siberian Division, Russian Academy of Sciences, Novosibirsk cluster@niic.nsc.ru 2Novosibirsk State University
Keywords: zinc, crystal structure, coordination polymers, metal-organic frameworks, carboxylic acids
Abstract >>
New layered metal-organic coordination polymers [Zn3(bpdc)3(DMA)2]·3DMA (1) (H2bpdc = 4,4′-bi-phenyldicaboxylic acid, DMA = N,N' -dimethylacetamide) and [Zn3(bdc) 3(im)2]·1.5H2O (2) (H2bdc = tere-phtalic acid, im = imidazole) are synthesized and characterized by X-ray crystallography.
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M. G. Voronkov1, A. A. Korlyukov2, D. R. Khamitova2, M. I. Buzin2, G. S. Samokhin1, T. A. Kochina1
1I. V. Grebenshchikov Institute of Silicate Chemistry, Russian Academy of Sciences, Saint-Petersburg t-kochina@mail.ru 2A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Moscow
Keywords: quasigermatranediol, molecular and crystal structure, X‑ray diffraction study, phase transition
Abstract >>
By X‑ray diffraction the crystal and molecular structure of quasigermatranediol (HO)2Ge(OCH2CH2)2NH at 155 K is determined. By quantum chemical method using second-order Møller–Plesset perturbation theory (MP2) and a split-valence 6-311++G(d,p) basis set with polarization and diffuse functions for all types of atoms, the structural parameters of this molecule are calculated. In the crystal, the quasigermatranediol molecules are arranged in columns due to O–H…O and N–H…O hydrogen bonds of medium strength. The columns are linked together via weak O–H…O and N–H…O hydrogen bonds. By calorimetry, the phase transition in a crystal of quasigermatranediol at 150-145 K is revealed.
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T. N. Drebushchak1,2, E. V. Boldyreva1,2, K. Fucke3,4
1Institute of Solid State Chemistry and Mechanochemistry, Siberian Division, Russian Academy of Sciences, Novosibirsk, Russia tanya@xray.nsu.ru 2Research and Education Center Molecular Design and Ecologically Safe Technologies, Novosibirsk State University, Novosibirsk, Russia 3Department of Chemistry, Durham University, United Kingdom 4Institute of Pharmacy, Innsbruck University, Innsbruck
Keywords: catechol compounds, hydrogen bonds, dihydrocaffeic acid, single-crystal X-ray diffraction
Abstract >>
Dihydrocaffeic acid Ñ9H10O4 is a natural antioxidant. The crystal structure of dihydrocaffeic acid is determined; the crystallographic data at 100 K are: a = 11.3189(4) Å, b = 5.5824(1) Å, c = 13.8431(4) Å, b = 109.248(4)°, and V = 825.80(4) Å3; the space group is P21/c, Z = 4. In addition to the formation of hydrogen bonds that are typical of acids, the compound has features that are important from the viewpoint of reactivity of dihydrocaffeic acid molecules. The position of one of the hydroxyl hydrogen atoms in the catechol group is disordered even at 100 K. The crystal structure of caffeic acid does not show such a disordering.
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E. E. Netreba, A. M. Fedorenko
Taurida National V. I.Vernadsky University, Simferepol, Ukraine evgtnu@gmail.com
Keywords: manganese(II), spirocarbon, coordination polymer, crystal structure, XRD
Abstract >>
A coordination polymer {[Mn(H2O)2(C11H20N4O2)2]2+⋅2(NO3–)}n is synthesized and its structure is determined. The crystals are monoclinic: space group P21/c, a = 12.3771(3) Å, b = 14.8775(3) Å, c = 18.1388(4) Å, β = 106.611(2)°, V = 3200.70(12) Å3, dx = 1.44 g/cm 3, Z = 4. Manganese ions are coordinated with four oxygen atoms of four organic ligands (two unique) and two water molecules. The coordination polyhedron is a distorted octahedron; the ΖMn–O angles between the adjacent oxygen atoms fall within 83.96(5)-98.11(5)°. The nitrate anions are in the outer coordination sphere. The Mn…Mn distances in the polymer are 8.56 Å. In the crystal, polymeric coordination chains are joined in layers perpendicular to the b axis by hydrogen bonds involving the organic ligands, water molecules, and nitrate anions.
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N. N. Golovnev1, M. S. Molokeev2, I. I. Golovneva1, G. A. Glushchenko2
1Siberian Federal University, Krasnoyarsk ngolovnev@sfu-kras.ru 2L. V. Kirensky Institute of Physics, Siberian Division, Russian Academy of Sciences, Krasnoyarsk
Keywords: crystal structure, enrofloxacinium cation, tetrabromidodichloridostannate(IV) anion , hydrogen bonds
Abstract >>
A new compound EnrH3[SnBr3.46Cl2.54]⋅H2O, where EnrH32+ is the enrofloxacinium cation (C19H24FN3O32+), is synthesized and its crystal and molecular structure is determined. Crystallographic data for enrofloxacinium tetrabromidodichloridostannate(IV) monohydrate are as follows: a = 17.1262(19) Å, b = 10.3435(11) Å, c = 17.2582(19) Å, β = 119.203(1)°, V = 2640.5(4) Å3, space group P21/c, Z = 4. Hydrogen bonds form a branched three-dimensional network linking EnrH32+, [SnBr3.46Cl2.54]2–, and water molecules. The structure is also stabilized by the π–π interaction of EnrH32+ aromatic rings.
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I. M. Sakhautdinov1, I. R. Batyrshin1, A. A. Fatykhov1, V. M. Yumabaeva2, K. Yu. Suponitskii3, M. Yu. Antipin3, M. S. Yunusov1
1Institute of Organic Chemistry, Ufa Scientific Center, Russian Academy of Sciences, Ufa ioh039@mail.ru 2Bashkir State University, Ufa 3A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Moscow
Keywords: methyl 4-[(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)methyl]-1-methyl-1H-pyrazol-5-carboxylate, methyl 4-[(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)methyl]-1-methyl-1H-pyrazol-3-carboxylate, NMR spectroscopy, X-ray crystallography
Abstract >>
The structure of methyl 4-[(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)methyl]-1-methyl-1H-pyrazol-5-carboxylate is determined by X-ray crystallography and further used to elucidate the structure of methyl 4-[(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)methyl]-1-methyl-1H-pyrazol-3-carboxylate, using the data of homo- and heteronuclear 2D NMR correlation spectroscopy.
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A. N. Enyashin, A. L. Ivanovskii
Institute of Solid State Chemistry, Ural Division, Russian Academy of Sciences, Ekaterinburg Enyashin@ihim.uran.ru
Keywords: layered molybdenum disulfide, nanostructures, polytypism, X-ray diffraction, simulation
Abstract >>
By the example of multilayer MoS2 nanotubes the capabilities of the X-ray diffraction method in determining possible polytypic forms of layered metal dichalcogenides, which may appear due to the nanostructuring of these compounds, are discussed. The conclusion about a low information value of the X-ray diffraction method is drawn, therefore the experimental analysis of the polytypic composition of nanostructures of metal dichalcogenides needs to attract electron microscopy and electronîé tomography methods.
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M. Hosseinifard1, L. Hashemi2, V. Amani1, A. Morsali2
1Department of Chemistry, Faculty of Sciences, Islamic Azad University, Shahr-e-Rey Branch, Tehran, Iran 2Department of Chemistry, Faculty of Sciences, Tarbiat Modares University, Tehran, Iran
Keywords: nanoparticle, 6,6'-dimethyl-2,2'-bipy, Zn(II), surfactant
Abstract >>
Two zinc(II) complexes [Zn(6,6'-dimethyl-2,2'-bipy)Cl2]n (1) and [Zn(6,6'-dimethyl-2,2'-bipy)I2]n (2) are synthesized from the reaction of the 6,6'-dimethyl-2,2'-bipy ligand with ZnCl2 and ZnI2. Zinc(II) oxide nanoparticles are synthesized by the thermolysis of [Zn(6,6'-dimethyl-2,2'-bipy)Cl2]n (1) and [Zn(6,6'-dimethyl-2,2'-bipy)I2]n (2) at two different temperatures. The ZnO nanoparticles are characterized by X-ray diffraction and scanning electron microscopy (SEM). SEM images show the average size of the ZnO nanoparticles produced of 50 nm and 60 nm in compounds 1 and 2 respectively.
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L. Yu. Izotova1, D. M. Ashurov1, S. A. Talipov1, B. T. Ibragimov1, E. Weber2
1A. S. Sadykov Institute of Bioorganic Chemistry, Uzbekistan Academy of Sciences, Tashkent, Uzbekistan l_izotova@yahoo.com 2Institute of Organic Chemistry, Freiberg Mining Academy, University of Technology, Freiberg, Germany
Keywords: 1,1'-binaphthyl-2,2'-bicarboxylic acid, solvation polymorphism, 2-picoline, crystal structure
Abstract >>
From solutions in 2-picoline (2-methylpyridine), depending on the temperature of crystallization, the universal clathratogen — 1,1'-binaphthyl-2,2'-bicarboxylic acid (BBA) — precipitates as crystals of three types with different composition and structure. Under normal conditions (room temperature), the precipitate is crystals of BBA disolvate with 2-picoline; a temperature reduction of 20°C results in the crystallization of monosolvate dihydrate; and a temperature increase of the same level results in the precipitation of monosolvate. That is, as the temperature of crystallization rises, the number of included guest molecules gradually decreases and the space where they are located becomes more closed. In 1:1:2 BBA/2-picoline/H2O solvate (space group P21/n, a = 11.991(2) Å, b = 9.317(2) Å, c = 22.283(5) Å, β = 99.77(3)°, V = 2453.3(9) Å3, Z = 4), the carboxyl groups of the BBA molecule at the Ñ21 atom are deprotonated and the released proton goes to the nitrogen atom of 2-picoline. BBA molecules interact with those of 2-picoline and water via H bonds to form infinite chains in direction [111], which, in their turn, join together into infinite two-dimensional sheets parallel to plane (–101). 2-Picoline molecules are located in the channels. In BBA/2-picoline disolvate (space group Ñ2/ñ, a = 11.7523(11) Å, b = 13.8563(13) Å, c = 17.9615(13) Å, β = 108.044(9)°, V = 2781.1(4) Å3, Z = 4), one BBA molecule and two H bond 2-picoline molecules form a 0-dimensional associate of the type G–H–G. The solvent molecules are also located in the channels. In BBA/2-picoline monosolvate (space group P21/ñ, a = 9.299(5) Å, b = 12.727(5) Å, c = 19.011(5) Å, β = 95.248(5)°, V = 2240.5(16) Å3, Z = 4), each BBA molecule is H-bonded with a 2-picoline molecule to form a 0-dimensional associate of the type H–G. Guest molecules are located in closed cavities.
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V. V. Ivanov, V. M. Talanov
South-Russian State Technical University, Novocherkassk valtalanov@mail.ru
Keywords: basic structural module, crystal structure type, modular structures, crystal structure codes
Abstract >>
A brief review of works on the crystal chemical features of the structure and methods of describing crystal structure types is presented. A variant of the universal system of a symbolic description of crystal structure types and modular structures with the use of structure codes is proposed. The structure code is based on a description of the geometry and topology of the basic structure module. Structure codes are intended for the identification and systematization of the structure types of compounds, the formalization of topological structural transformations, the determination of structural modules, and the derivation of genetic relationships between the structures.
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B. Jović, A. Nikolić, B. Holló
Department of Chemistry, Faculty of Sciences, University of Novi Sad, Novi Sad, Serbia branislav.jovic@dh.uns.ac.rs
Keywords: hydrogen bonding, N-substituted caproamide, tetrahydrofuran, DFT
Abstract >>
The results are reported of a study of hydrogen bonding between various N-substituted caproamides and tetrahydrofuran as an O-electron donor by means of FTIR spectroscopy. The spectroscopic characteristics for N—H…O hydrogen bonded complexes are given. The B3LYP functional with 6-31G** basis set has been used to calculate the structural parameters of the studied hydrogen bonded complexes. It can be assumed that both inductive and steric effects play an important role in the stability of these hydrogen bonded complexes.
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M.N. Arshad1, O. Åžahin2, M. Ziaur-Rehman3, I.U. Khan4, A.M. Asiri1, H.M. Rafique5
1Department of Chemistry & Center of Excellence for Advanced Materials Research (CEAMR) Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia 2Scientific and Technological Research Application and Research Center, Sinop University, Sinop, Turkey onurs@omu.edu.tr 3Applied Chemistry Research Center, PCSIR, Laboratories Complex Ferozpur Road, Lahore, Pakistan 4Materials Chemistry Laboratory, Department of Chemistry, GC University, Lahore, Pakistan 5X-ray Diffraction and Crystallography Laboratory, Department of Physics, School of Physical Sciences, University of the Punjab, Lahore, Pakistan
Keywords: X-ray diffraction analysis, benzothiazine, oxalohydrazide, DFT, Mulliken atomic charge, molecular electrostatic potential
Abstract >>
The title compound, 4-hydroxy-2H-1,2-benzothiazine-3-carbohydrazide 1,1-dioxide-oxalohydrazide (1:1), is determined using X-ray diffraction techniques and the molecular structure is also optimized at the B3LYP/6-31G( d, p) level using density functional theory (DFT). The asymmetric unit consists of four independent molecules. The oxalohydrazide molecules have the centre of symmetry at the mid-point of the central C—C bond. Each thiazine ring adopts a half-chair conformation. Intermolecular C—H…O, N—H…O and N—H…N hydrogen bonds produce R22(10), R22(13), R33(12) and R33(15) rings, which lead to one-dimensional polymeric chains. An extensive three-dimensional supramolecular network of N—H…N, N—H…O, C—H…O and O—H…O hydrogen bonds is responsible for crystal structure stabilization.
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S. B. Artemkina1, N. G. Naumov1, A. V. Virovets2, V. A. Daletskii2, S. G. Kozlova1, V. E. Fedorov1
1A. V. Nikolaev Institute of Inorganic Chemistry, Siberian Division, Russian Academy of Sciences, Novosibirsk, Novosibirsk State Research University
artem@niic.nsc.ru
2A. V. Nikolaev Institute of Inorganic Chemistry, Siberian Division, Russian Academy of Sciences, Novosibirsk
Keywords: niobium, cluster, synthesis, crystal structure, magnetic properties, spin-orbit interactionå
Abstract >>
A cluster complex Cs3Nb2I9 is obtained by a high-temperature reaction of niobium, iodine, and cesium iodide. Its crystal structure is determined: trigonal space group P63/mmc, a = 8.2463(3) Å, c = 19.5419(14) Å, V = 1150.84(10) Å3, R( F) = 0.0614. The compound obtained is characterized by temperature independent paramagnetism in the temperature range 70-290 K.
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V. P. Korolev
G. A. Krestov Institute of Solution Chemistry, Russian Academy of Sciences, Ivanovo korolev@isuct.ru
Keywords: sodium chloride, urea, glycine, aqueous solutions, partial volumes, hydration numbers
Abstract >>
The hydration number of the glycine amino acid in aqueous sodium chloride solution is less than in aqueous urea solution; the difference increases significantly with increasing concentration of the nonaqueous component. Given the same partial volume of water, the hydration numbers of glycine in the two systems are close together (δ ≈ 5%).
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M. N. Sokolov1,2, A. V. Rogachev1, A. V. Virovets1, S. S. Yarovoi1, Yu. V. Mironov1, V. P. Fedin1,2
1A. V. Nikolaev Institute of Inorganic Chemistry, Siberian Division, Russian Academy of Sciences, Novosibirsk caesar@niic.nsc.ru 2Novosibirsk State University
Keywords: niobium, sulfur, bromine, polymorphism, crystal structure
Abstract >>
The crystal structures of triclinic and monoclinic modifications of Nb thiobromide NbS2Br2 are determined by X-ray analysis. Both modifications possess layered structures in which {Nb2(µ-S2)2}4+ cluster units are connected by bridging bromides into 2D layers ∞2[Nb2(S2)2Br8/2]. The two polymorphs differ only in the way in which the layers are stacked. Interatomic distances and bond angles are identical for both polymorphs.
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V. Anyushin1,2, M. N. Sokolov1,2, E. V. Peresypkina1, V. P. Fedin1,2
1A. V. Nikolaev Institute of Inorganic Chemistry, Siberian Division, Russian Academy of Sciences, Novosibirsk caesar@niic.nsc.ru 2Novosibirsk State University
Keywords: tantalum, bromine, cluster, X-ray structure, hydrogen bonds
Abstract >>
The crystal structure of the [Ta6Br12(H2O)6](BPh4)2⋅4H2O salt (1), obtained from Ta6Br14⋅7H2O and NaBPh4, is determined by X-ray crystallographic analysis. The structure contains a network of hydrogen bonds, which organizes the cluster cations into layers.
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Ya. M. Gaifulin, A. I. Smolentsev, Yu. V. Mironov
V. Nikolaev Institute of Inorganic Chemistry, Siberian Division, Russian Academy of Sciences, Novosibirsk yuri@niic.nsc.ru
Keywords: rhenium, bioctahedral cluster complex, nickel, crystal structure
Abstract >>
A rhenium cluster complex [Ni(NH3)6]2.5⋅NH4[Re12CS17(CN)6]⋅8.5H2O is obtained and structurally described. The compound crystallizes in the triclinic space group P-1 with the unit cell parameters: a = 11.0856(13) Å, b = 15.242(2) Å, c = 21.232(3) Å, α = 90.158(4)°, β = 97.439(4)°, γ = 90.051(4)°, V = 3557.3(8) Å3, Z = 2, dcalc = 3.287 g/cm3. The crystal structure represents a packing of [Ni(NH3)6]2+ and NH4+ cations, [Re12CS17(CN)6]6– cluster anions, and crystallization water molecules bound by a system of hydrogen bonds.
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S. M. Aldoshin1, Z. G. Aliev1, A. A. Astrat’ev2, T. K. Goncharov1, D. V. Dashko2, Yu. M. Milekhin3, A. I. Stepanov2, N. I. Shishov3
1Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka aliev@icp.ac.ru 2Special Construction-Technological Bureau “Tekhnolog”, Saint Petersburg stepanoff@pisem.net 3Federal Center for Dual-Use Technologies “Soyuz”, Dzerzhinskii
Keywords: oxadiazole, furazan, crystal structure
Abstract >>
The crystal structure of a new energetic compound of 4,4"-dinitro-[3,3':4,3"]-tris-[1,2,5]-oxadiazole is studied.
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L. I. Vlasova1, N. Z. Baibulatova1, S. A. Grabovski1, M. Haukka2, V. A. Dokichev1, Yu. V. Tomilov3
1Institute of Organic Chemistry, Ufa Scientific Center, Russian Academy of Sciences, Ufa dokichev@anrb.ru 2Department of Chemistry, University of Eastern Finland, Joensuu, Finland 3N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow
Keywords: single crystal X‑ray diffraction study, 3,7-dimethyl-9-thia-3,7-diazabicyclo[3.3.1]nonane-9,9-dioxide
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By a single crystal X‑ray diffraction study the molecular structure of 3,7-dimethyl-9-thia-3,7-diazabicyclo[3.3.1]nonane-9,9-dioxide having a chair-chair conformation with a diequatorial arrangement of methyl groups at nitrogen atoms is determined. Compound 1 C8H16N2O2S crystallizes in the space group Pnma with the following cell parameters: a = 11.0262(3) Å, b = 14.4490(3) Å, c = 6.1780(3) Å.
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Yu. R. Galina1, A. N. Lobov1, R. M. Sultanova1, L. V. Spirikhin1, V. A. Dokichev1, K. Yu. Suponitsky2
1Institute of Organic Chemistry, Ufa Scientific Center, Russian Academy of Sciences, Ufa dokichev@anrb.ru 2A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Moscow
Keywords: 5-diazo-exo-3-azatricyclo[5.2.1.0 2,6]decane-4-one, phosphazines, molecular structure, single crystal X‑ray diffraction study
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The molecular structure of 5-[(triphenylphosphoranylidene)hydrazono]-exo-3-azatricyclo[5.2.1.02.6]decane-4-one is determined. The C27H26N3OP compound crystallizes in the space group P-1: a = 9.2163(9) Å, b = 11.1102(11) Å, c = 11.9397(12) Å, α = 74.284(2)°, β = 78.532(2)°, γ = 72.004(2)°.
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R.M. Bellabarba1, M. Nieuwenhuyzen2, G.C. Saunders3
1Current address: Sasol Technology (UK) Ltd, Purdie Building, North Haugh, St Andrews, KY16 9ST, United Kingdom 2The School of Chemistry, Queen¢s University Belfast, David Keir Building, Belfast, BT9 5BA, United Kingdom 3Department of Chemistry, The University of Waikato, Private Bag 3105, Hamilton 3240, New Zealand g.saunders@waikato.ac.nz
Keywords: conglomerate, η5-pentamethylcyclopentadienyl, iridium, X-ray structure
Abstract >>
The salt (η5-pentamethylcyclopentadienyl){bis(pentafluorophenyl)thiomethylphenylphosphine-κ2S,P)chloroiridium(III) tetrafluoroborate, [(η5-C5Me5)IrCl{κ2S,P-(C6F5)2PC6H4SMe-2}]BF4, crystallizes as a conglomerate in the orthorhombic crystal system in space group P212121 with unit cell parameters a = 9.9621(9) Å, b = 16.7793(15) Å, c = 18.5040(16) Å, V = 3093.1(5) Å3, Z = 4, dcalc = 2.014 g⋅cm–3. The structure of the SIr, SS stereoisomer reveals three-legged piano stool geometry about Ir, with Cp*—Ir, Ir—P, Ir—S and Ir—Cl distances of 1.847(5), 2.2791(14), 2.3451(13) and 2.3840(12) Å respectively.
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D.J. Price1, S.J. Coles2, M.B. Hursthouse2,3
1WestCHEM, School of Chemistry, University of Glasgow, Glasgow, United Kingdom Daniel.Price@glasgow.ac.uk 2School of Chemistry, University of Southampton, Southampton, United Kingdom 3Department of Chemistry, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia
Keywords: cobalt, layered compound, carboxylate bridge, pseudopolymorphism
Abstract >>
Reaction of cobalt hydroxide with the α,ω-dicarboxylic acid and 1,12-dodecanedioic acid under ambient conditions results in the formation of a trihydrate Co(C12H20O4)(H2O)3 (1). Single crystal X-ray diffraction studies show 1 to crystallise in the orthorhombic space group Pccn with cell parameters a = 40.2343(7) Å, b = 8.1519(1) Å, c = 9.1011(2) Å. The structure has a very pronounced two dimensional character, with a separation of hydrophobic n-alkyl chains from the carboxylate groups, the Co2+ cations and the water of crystallisation. The structure is discussed in respect of the structures of other known compositionally related compounds, including the dihydrate Co(C12H20O4)(H2O)2.
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