scholarly journals Cocrystals of 2-Aminopyrimidine with Boric Acid—Crystal Engineering of a Novel Nonlinear Optically (NLO) Active Crystal

Crystals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 403 ◽  
Author(s):  
Matouš Kloda ◽  
Irena Matulková ◽  
Ivana Císařová ◽  
Petra Becker ◽  
Ladislav Bohatý ◽  
...  
Keyword(s):  
Boric Acid ◽  
Crystal Engineering ◽  
Second Harmonic ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Fundamental Laser ◽  
Powder Samples ◽  
Group 2 ◽  
Ft Raman

Crystal engineering of novel materials for nonlinear optics (NLO) based on 2-aminopyrimidine yielded two molecular cocrystals with boric acid—trigonal (P3221 space group) 2-aminopyrimidine—boric acid (3/2) and monoclinic (C2/c space group) 2-aminopyrimidine—boric acid (1/2). In addition to crystal structure determination by single crystal X-ray diffraction, the cocrystals were characterized by powder X-ray diffraction and vibrational spectroscopy (FTIR and FT Raman). Large single crystals of the non-centrosymmetric cocrystal 2-aminopyrimidine—boric acid (3/2) were grown to study the optical properties and determine the second harmonic generation (SHG) efficiency (using 800 nm fundamental laser line) of powder samples.

Powder X-Ray Diffraction Data for Ca2Bi2O5and C4Bi6O13

1992 ◽  
Vol 7 (2) ◽  
pp. 109-111 ◽  
Author(s):  
C.J. Rawn ◽  
R.S. Roth ◽  
H.F. McMurdie
Keyword(s):  
Powder Diffraction ◽  
Diffraction Data ◽  
Neutron Powder Diffraction ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Cell Dimensions ◽  
Powder Samples ◽  
Orthorhombic Cell ◽  
Unit Cell Dimensions

AbstractSingle crystals and powder samples of Ca2Bi5O5and Ca4Bi6O13have been synthesized and studied using single crystal X-ray diffraction as well as X-ray and neutron powder diffraction. Unit cell dimensions were calculated using a least squares analysis that refined to a δ2θof no more than 0.03°. A triclinic cell was found with space group , a = 10.1222(7), b = 10.1466(6), c = 10.4833(7) Å. α= 116.912(5), β= 107.135(6) and γ= 92.939(6)°, Z = 6 for the Ca2Bi2O5compound. An orthorhombic cell was found with space group C2mm, a = 17.3795(5), b = 5.9419(2) and c = 7.2306(2) Å, Z = 2 for the Ca4Bi6O13compound.

Boron Carbide B25C and B8C18 Synthesized Using Boric Acid-Glucose and Boric Acid-Active Carbon at Low Temperature without Coreductor Materials

2014 ◽  
Vol 896 ◽  
pp. 609-612 ◽  
Author(s):  
Mufirah Cahya Fajrah Toana ◽  
Bambang Soegijono
Keyword(s):  
Boron Carbide ◽  
Boric Acid ◽  
Diffraction Pattern ◽  
Active Carbon ◽  
Lattice Parameters ◽  
X Ray Diffraction ◽  
Absorption Bands ◽  
Space Group ◽  
X Ray ◽  
Crystal System

This study examines the formation of Boron carbide with a wide homogeneity range B8C18 and B25C, from boric acid-glucose and boric acid-active carbon as precursor materials. The samples was analysed by means of X-ray diffraction and Fourier Transform Infrared spectrometer. X-ray diffraction pattern was analysed by GSAS software. X ray diffraction pattern of B8C18 shows peaks at 27o, 39o, 45o, 65o and 79o, orthorhombic crystal system and lattice parameters a = 13.640 Ǻ, b = 7.8500 Ǻ and c = 12.910 Ǻ and space group P212121, whereas for B25C sample show peaks at 2θ angle 28o and 40o, tetragonal crystal system, and the lattice parameters a = b = 8.753 Ǻ and c = 5.093 Ǻ and space group P-4 2 m. FTIR results show that for B8C18 have absorption bands with B-C bond at 1196.5 cm-1, 0-H 3216.7 cm-1 and B-O at 1477.1 cm-1, whereas the formation B25C have absorption bands with B-C bond at 1195.1 cm-1, O-H 3216.7 cm-1 and B-O 1460.8 cm-1.

Darstellung, Reaktivität und Kristallstruktur von [(CO)3Mn(dppm)2(μ-S)Rh(CO)] / Synthesis, Reactivity and Crystal Structure of [(CO)3Mn(dppm)2(μ-S)Rh(CO)]

1992 ◽  
Vol 47 (5) ◽  
pp. 668-674 ◽  
Author(s):  
O. Heyke ◽  
G. Beuter ◽  
I.-P. Lorenz
Keyword(s):  
Crystal Structure ◽  
Mass Spectra ◽  
Frame Structure ◽  
Dimeric Complex ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
H Nmr ◽  
Group 2

The reaction of [(CO)3Mn(dppm)2Rh(CO)] (1) with H2S in dichloromethane yields [(CO)3Mn(dppm)2(μ-S)Rh(CO)] (2), which is characterized by IR, 31P{1H}, 1H, 13C{1H} nmr and mass spectra. The crystal structure of 2 was determined by X-ray diffraction: space group P21/n, Z = 4, a = 1232.6(3), b = 2558.8(4), c = 1640.8(2) pm, β = 97.74(2)°, R/Rw = 0.048/0.057. The dimeric complex shows A-frame structure possessing a bridging sulfur and a semibridging CO group. 2 cannot be oxidized to the corresponding SO2 bridged complex [(CO)3Mn(dppm)2(μ-SO2)Rh(CO)] (3). The reaction of 2 with SO2, however, yields the SO2 bridged complex [(CO)2Mn(dppm)2(μ-S)(μ-SO2)Rh(CO)] (5); in dichloromethane 2 is readily chlorinated to afford the salt [(CO)3Mn(dppm),(μ-S)RhCl]Cl (4).

Structural studies of dithiatetrazocines: X-ray crystal structures of the symmetric dithiatetrazocines p-XC6H4CN4S2CC6H4X [X = NO2, Br] and the first unsymmetric dithiatetrazocine, p-BrC6H4CN4S2CC6H4NO2

2002 ◽  
Vol 80 (11) ◽  
pp. 1507-1517 ◽  
Author(s):  
Andrew D Bond ◽  
Delia A Haynes ◽  
Jeremy M Rawson
Keyword(s):  
Intermolecular Interactions ◽  
Crystal Engineering ◽  
Molecular Electrostatic Potential ◽  
Monoclinic Space Group ◽  
Molecular Electrostatic Potentials ◽  
X Ray Diffraction ◽  
Triclinic Space Group ◽  
Space Group ◽  
X Ray ◽  
Triclinic Phase

Oxidation of equimolar amounts of [p-BrC6H4CNSSN]Cl and [p-O2NC6H4CNSSN]Cl with elemental O2 in the presence of Ph3Sb in MeCN yields a mixture of the symmetric dithiatetrazocines, O2NC6H4CN4S2CC6H4NO2 (1) and BrC6H4CN4S2CC6H4Br (2) as well as the unsymmetrically substituted derivative BrC6H4CN4S2CC6H4NO2 (3). The structures of compounds 1–3 are determined by X-ray diffraction: 1 crystallizes in the monoclinic space group P21/c (a = 8.6397(4), b = 5.8359(4), c = 14.9767(11) Å, β = 92.088(4)°) with half a molecule in the asymmetric unit; 2 crystallizes in the triclinic space group P[Formula: see text] (a = 6.5330(5), b = 8.2084(6), c = 14.7264(9) Å, α = 84.483(4)°, β = 77.112(4)°, γ = 87.879(3)°); 3 was found to crystallize in two forms: recrystallization from CH2Cl2 at room temperature yielded a solvent-free, triclinic phase, space group P[Formula: see text] (a = 6.5060(9), b = 7.0739(9), c = 9.1164(8) Å, α = 81.860(3)°, β = 83.406(5)°, γ = 66.589(5)°), whereas cooling a solution to –5°C yielded a solvated form, 3·CH2Cl2, which crystallizes in the monoclinic space group P21/m (a = 6.179(1), b = 10.960(2), c = 13.884(3) Å, β = 92.69(3)°). The NO2···Br intermolecular interactions observed in the unsolvated structure of 3 are disrupted in the solvate structure; the CH2Cl2 molecule in the latter is aligned such that its molecular dipole interacts with both nitro and bromo groups, retaining a molecular chain motif. The structures are discussed in relation to their semi-empirically calculated molecular electrostatic potentials and calculations of intermolecular interactions using van der Waals forces combined with an electrostatic point charge model.Key words: dithiatetrazocine, crystal structure, crystal engineering, molecular electrostatic potential.

Crystal structure of an inclusion complex between chiral monoaza-15-crown-5 and S(–)-1-phenyl-ethyl ammonium percholorate

2003 ◽  
Vol 218 (5) ◽  
Author(s):  
Süheyla Özbey ◽  
F. B. Kaynak ◽  
M. Toğrul ◽  
N. Demirel ◽  
H. Hoşgören
Keyword(s):  
Crystal Structure ◽  
Inclusion Complex ◽  
Single Crystal ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
New Type

AbstractA new type of inclusion complex, S(–)-1 phenyl ethyl ammonium percholorate complex of R-(–)-2-ethyl - N - benzyl - 4, 7, 10, 13 - tetraoxa -1- azacyclopentadecane, has been prepared and studied by NMR, IR and single crystal X-ray diffraction techniques. The compound crystallizes in space group

Crystal structure determination of the conformation of two bicyclo[3.3.1]nonan-ones

1985 ◽  
Vol 63 (6) ◽  
pp. 1166-1169 ◽  
Author(s):  
John F. Richardson ◽  
Ted S. Sorensen
Keyword(s):  
Crystal Structure ◽  
Direct Methods ◽  
Chair Conformation ◽  
Molecular Structures ◽  
Boat Conformation ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Final Agreement

The molecular structures of exo-7-methylbicyclo[3.3.1]nonan-3-one, 3, and the endo-7-methyl isomer, 4, have been determined using X-ray-diffraction techniques. Compound 3 crystallizes in the space group [Formula: see text] with a = 15.115(1), c = 7.677(2) Å, and Z = 8 while 4 crystallizes in the space group P21 with a = 6.446(1), b = 7.831(1), c = 8.414(2) Å, β = 94.42(2)°, and Z = 2. The structures were solved by direct methods and refined to final agreement factors of R = 0.041 and R = 0.034 for 3 and 4 respectively. Compound 3 exists in a chair–chair conformation and there is no significant flattening of the chair rings. However, in 4, the non-ketone ring is forced into a boat conformation. These results are significant in interpreting what conformations may be present in the related sp2-hybridized carbocations.

scholarly journals X-ray diffraction analysis of matter taking into account the second harmonic in the scattering of powerful ultrashort pulses of an electromagnetic field

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
M. K. Eseev ◽  
A. A. Goshev ◽  
K. A. Makarova ◽  
D. N. Makarov
Keyword(s):  
Electromagnetic Field ◽  
Diffraction Analysis ◽  
Diffraction Pattern ◽  
Second Harmonic ◽  
Ultrashort Pulses ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scattering Spectra ◽  
Technical Possibility ◽  
2D And 3D

AbstractIt is well known that the scattering of ultrashort pulses (USPs) of an electromagnetic field in the X-ray frequency range can be used in diffraction analysis. When such USPs are scattered by various polyatomic objects, a diffraction pattern appears from which the structure of the object can be determined. Today, there is a technical possibility of creating powerful USP sources and the analysis of the scattering spectra of such pulses is a high-precision instrument for studying the structure of matter. As a rule, such scattering occurs at a frequency close to the carrier frequency of the incident USP. In this work, it is shown that for high-power USPs, where the magnetic component of USPs cannot be neglected, scattering at the second harmonic appears. The scattering of USPs by the second harmonic has a characteristic diffraction pattern which can be used to judge the structure of the scattering object; combining the scattering spectra at the first and second harmonics therefore greatly enhances the diffraction analysis of matter. Scattering spectra at the first and second harmonics are shown for various polyatomic objects: examples considered are 2D and 3D materials such as graphene, carbon nanotubes, and hybrid structures consisting of nanotubes. The theory developed in this work can be applied to various multivolume objects and is quite simple for X-ray structural analysis, because it is based on analytical expressions.

Single-crystal investigation of Ce5AgxGe4−x (x = 0.1−1.08) with Sm5Ge4 type

2020 ◽  
Vol 75 (8) ◽  
pp. 765-768
Author(s):  
Bohdana Belan ◽  
Dorota Kowalska ◽  
Mariya Dzevenko ◽  
Mykola Manyako ◽  
Roman Gladyshevskii
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Diffraction Data ◽  
Binary Compound ◽  
Lattice Parameters ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray

AbstractThe crystal structure of the phase Ce5AgxGe4−x (x = 0.1−1.08) has been determined using single-crystal X-ray diffraction data for Ce5Ag0.1Ge3.9. This phase is isotypic with Sm5Ge4: space group Pnma (No. 62), Pearson code oP36, Z = 4, a = 7.9632(2), b = 15.2693(5), c = 8.0803(2) Å; R1 = 0.0261, wR2 = 0.0460, 1428 F2 values and 48 variables. The two crystallographic positions 8d and 4c show Ge/Ag mixing, leading to a slight increase in the lattice parameters as compared to those of the pure binary compound Ce5Ge4.

New mixed-valent alkali chain sulfido ferrates A1+x[FeS2] (A = K, Rb, Cs; x = 0.333–0.787)

2020 ◽  
Vol 235 (8-9) ◽  
pp. 275-290
Author(s):  
Michael Schwarz ◽  
Pirmin Stüble ◽  
Katharina Köhler ◽  
Caroline Röhr
Keyword(s):  
Alkali Metal ◽  
General Structure ◽  
Variable Number ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Modulated Structure ◽  
Space Group ◽  
X Ray ◽  
Local Coordination ◽  
Natural Pyrite

AbstractFour new mixed-valent chain alkali metal (A) sulfido ferrates of the general structure family ${A}_{1+x}\left[{\text{Fe}}_{x}^{\text{II}}{\text{Fe}}_{1-x}^{\text{III}}{\text{S}}_{2}\right]$ were synthesized in the form of tiny green-metallic needles from nearly stoichiometric melts reacting elemental potassium with natural pyrite (A = K) or previously prepared Rb2S/Cs2S2 with elemental iron and sulfur (A = Rb/Cs). The crystal structures of the compounds were determined by means of single crystal X-ray diffraction: In the (3+1)D modulated structure of K7.15[FeS2]4 (space group Ccce(00σ3)0s0, a = 1363.87(5), b = 2487.23(13), c = 583.47(3) pm, q = 0,0,0.444, R1 = 0.055/0.148, x = 0.787), a position modulation of the two crystallographically different undulated ${}_{\infty }{}^{1}\left[{\text{FeS}}_{4/2}\right]$ tetrahedra chains and the surrounding K cations is associated with an occupation modulation of one of the three potassium sites. In the case of the new monoclinic rubidium ferrate Rb4[FeS2]3 (x = $\frac{1}{3}$; space group P21/c, a = 1640.49(12), b = 1191.94(9), c = 743.33(6) pm, β = 94.759(4)°, Z = 4, R1 = 0.1184) the undulation of the tetrahedra chain is commensurate, the repetition unit consists of six tetrahedra. In the second new Rb ferrate, Rb7[FeS2]5 (x = 0.4; monoclinic, space group C2/c, K7[FeS2]5-type; a = 2833.9(2), b = 1197.36(9), c = 744.63(6) pm, β = 103.233(4)°, Z = 4, R1 = 0.1474) and its isotypic mixed Rb/Cs-analog Rb3.6Cs3.4[FeS2]5 (a = 2843.57(5), b = 1226.47(2), c = 759.890(10) pm, β = 103.7170(9)°, R1 = 0.0376) the chain buckling leads to a further increased repetition unit of 10 tetrahedra. For all mixed-valent ferrates, the Fe–S bond lengths continuously increase with the amount (x) of Fe(II). The buckling of the chains is controlled through the local coordination of the S atoms by the variable number of A cations of different sizes.

Strukturuntersuchungen an Diaryldichalkogeniden: Die Molekülstrukturen von [2,4,6-(CF3)3C6H2S]2,[2,4,6-Me3C6H2Te]2 und [2-Me2N-4,6-(CF3)2C6H2Te]2 / Structural Investigations of Diaryl Dichalcogenides: The Molecular Structures of [2,4,6-(CF3)3C6H2S]2, [2,4,6-Me3C6H2Te]2 and [2-Me2N-4,6-(CF3)2C6H2Te]2

1992 ◽  
Vol 47 (3) ◽  
pp. 305-309 ◽  
Author(s):  
Anja Edelmann ◽  
Sally Brooker ◽  
Norbert Bertel ◽  
Mathias Noltemeyer ◽  
Herbert W. Roesky ◽  
...  
Keyword(s):  
Molecular Structures ◽  
Monoclinic Space Group ◽  
Crystal Data ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
Structural Investigations ◽  
Space Group ◽  
X Ray

Abstract The Molecular Structures of [2,4,6-(CF3)3C6H2S]2 (1) [2,4,6-Me3C6H2Te]2 and [2-Me2N-4,6-(CF3)2C6H2Te]2 (3) have been determined by X-ray diffraction. Crystal data: 1: orthorhombic, space group P212121, Z = 4, a = 822.3(2), b = 1029.2(2), c = 2526.6(5) pm (2343 observed independent reflexions, R = 0.042); 2: orthorhombic, space group Iba 2, Z = 8, a = 1546.5(2), b = 1578.4(2), c = 1483.9(1) pm (2051 observed independent reflexions, R = 0.030); 3: monoclinic, space group P 21/c, Z = 4, a = 1118.7(1), b = 1536.5(2), c = 1492.6(2) pm, β = 98.97(1)° (3033 observed independent reflexions, R = 0.025).

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