Raman-Spektren eines AsJ3-Einkristalls und von SbJ3-und BiJ3-Kristallpulvern / Raman spectra of an AsJ3-single crystal and of SbJ3- and BiJ3--crystal powders

1970 ◽  
Vol 25 (7) ◽  
pp. 1101-1107 ◽  
Author(s):  
W. Kiefer
Keyword(s):  
Single Crystal ◽  
Raman Spectra ◽  
Ruby Laser ◽  
Factor Group ◽  
Unit Cell ◽  
Space Group ◽  
Polarization Measurements ◽  
Double Monochromator ◽  
Depolarization Ratios

Raman spectra of an AsJ3-single crystal were recorded using a quasicontinuous ruby laser, a double monochromator and a special registration electronics. The polarization measurements allow the assignments of the internal, translational and rotational modes of AsJ3 (factor group S6). Since SbJ3 and BiJ3 have the same space group and the same number of molecules per unit cell, one can assign the wavenumbers of the crystal powder Raman spectra in analogy to AsJ3. The depolarization ratios of the Raman lines of AsJ3 in solutions were also determined

X-ray powder diffraction data for estra-4,9-diene-3,17-dione, C18H22O2

2020 ◽  
Vol 35 (4) ◽  
pp. 282-285
Author(s):  
Zhicheng Zha ◽  
Ting Tang ◽  
Xiaoyan Bian ◽  
Qing Wang
Keyword(s):  
Single Crystal ◽  
Cell Volume ◽  
Powder Diffraction ◽  
Structure Data ◽  
Diffraction Data ◽  
Unit Cell Volume ◽  
Unit Cell ◽  
Powder Diffraction Data ◽  
Space Group ◽  
X Ray

X-ray powder diffraction data for estra-4,9-diene-3,17-dione, C18H22O2, are reported [a = 9.236(7) Å, b = 10.294(4) Å, c = 15.471(1) Å, unit cell volume V = 1471.11 Å3, Z = 4, and space group P212121]. All measured lines were indexed and are consistent with the P212121 space group. No detectable impurities were observed. The single-crystallographic data of the compound are also reported [a = 9.2392(7) Å, b = 10.2793(5) Å, c = 15.4822(7) Å, unit cell volume V = 1470.37(15) Å3, Z = 4, and space group P212121]. Both single-crystal and powder diffraction methods can get the similar structure data.

Raman study of the structural properties of KNO3(II)

1977 ◽  
Vol 55 (7) ◽  
pp. 1242-1250 ◽  
Author(s):  
M. H. Brooker
Keyword(s):  
Single Crystals ◽  
Structural Properties ◽  
Raman Spectra ◽  
Excellent Agreement ◽  
Room Temperature ◽  
Group Analysis ◽  
Factor Group ◽  
Spectral Features ◽  
Space Group ◽  
Raman Study

Raman spectra of oriented single crystals of KNO3(II) have been recorded at 298 and 77 K. At both temperatures the data are in excellent agreement with the factor group analysis based on the generally accepted Pmcn space group. Additional spectral features observed near room temperature suggest the presence of a significant number of disordered nitrate groups on alternate lattice sites, although the majority of nitrate groups occupy the ordered sites. As the temperature is lowered, the disordered groups freeze out until near the temperature of reported electrical anomalies (213 K) only the ordered sites are occupied. Improved resolution has resulted in detection of a number of new spectral features while improved depolarization data have resulted in reassignment of several peaks.

Notizen: Solid State Structure of N,N-Dibenzylhydroxylamine

1995 ◽  
Vol 50 (4) ◽  
pp. 699-701 ◽  
Author(s):  
Norbert W. Mitzel ◽  
Jürgen Riede ◽  
Klaus Angermaier ◽  
Hubert Schmidbaur
Keyword(s):  
Solid State ◽  
Hydrogen Bonds ◽  
Single Crystal ◽  
Unit Cell ◽  
Monoclinic Space Group ◽  
State Structure ◽  
X Ray Diffraction ◽  
Space Group ◽  
Solid State Structure ◽  
X Ray

The solid-state structure of N,N-dibenzylhydroxylamine (1) has been determined by single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P 21/n with four formula units in the unit cell. N,N-dibenzylhydroxylamine dimerizes to give N2O2H2 sixmembered rings as a result of the formation of two hydrogen bonds O - H ··· N in the solid state.

[Al2P4]6-, [Al2As4]6-, [Ga2P4]6- und [Ga2As4]6-, Zintl-Anionen mit 1,3-Dimethylencyclobutan-Struktur / [Al2P4]6-, [Al2As4]6-, [Ga2P4]6- and [Ga2As4]6-, Zintl Anions with 1.3-Dimethylene-cyclobutane Structure

1991 ◽  
Vol 46 (6) ◽  
pp. 789-794 ◽  
Author(s):  
M. Somer ◽  
D. Thiery ◽  
K. Peters ◽  
L. Walz ◽  
M. Hartweg ◽  
...  
Keyword(s):  
Bond Order ◽  
Factor Group ◽  
Unit Cell ◽  
Normal Coordinate Analysis ◽  
Monoclinic Space Group ◽  
Partial Structure ◽  
Normal Coordinate ◽  
Space Group ◽  
Single Bonds ◽  
Fir Spectra

The compounds Cs6M2X4 (M = Al, Ga; X = P, As) were synthesized from stoichiometric mixtures of Cs, M and Cs4X6 in sealed Nb ampoules at 950 K. They are isotypic and crystallize in the monoclinic space group P21/c (No. 14) with Z = 4 formula units per unit cell. The anion partial structure is characterized by isolated [M2X4]6- units with relatively short distances for the terminal d(M–X) bonds corresponding to a Pauling Bond Order PBO = 1.5. The distances d(M–X) of the four-membered M2X2 rings correspond to single bonds.The FIR spectra have been interpreted on the basis of the [M2X4]6- units with 2/m 2/m 2/m-D2h, symmetry by considering a factor group splitting. The assignment of the observed frequencies is supported by a normal coordinate analysis.

Orthoborate Halides with the Formula (M+II)5(BO3)3X: Syntheses, Crystal Structures and Raman Spectra of Eu5(BO3)3Cl and Ba5(BO3)3X (X = Cl, Br)

2011 ◽  
Vol 66 (4) ◽  
pp. 359-365 ◽  
Author(s):  
Olaf Reckeweg ◽  
Armin Schulz ◽  
Francis J. DiSalvo
Keyword(s):  
Single Crystal ◽  
Single Crystals ◽  
Crystal Structures ◽  
Raman Spectra ◽  
Direct Synthesis ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
X Ray ◽  
Incremental Volume

Single crystals of Eu5(BO3)3Cl were obtained by serendipity by reacting Eu2O3 and Mg with B2O3 at 1300 K in the presence of an NaCl melt for 13 h in silica-jacketed Nb ampoules. Ba5(BO3)3X (X = Cl, Br) crystals were formed by direct synthesis from appropriate amounts of Ba(OH)2, H3BO3 and the respective barium halide (hydrate) in alumina crucibles kept in the open atmosphere at 1300 K for 13 h. The crystal structures of the title compounds were determined with single-crystal X-ray diffraction. All compounds crystallize isotypically to Sr5(BO3)3Cl in the orthorhombic space group C2221 (no. 20, Z = 4) with the lattice parameters a = 1000.34(7), b = 1419.00(9), c = 739.48(5) pm for Eu5(BO3)3Cl, a = 1045.49(5), b = 1487.89(8), c = 787.01(4) pm for Ba5(BO3)3Cl, and a = 1048.76(7), b = 1481.13(9) and c = 801.22(5) pm for Ba5(BO3)3Br. The Raman spectra of all compounds were acquired and are presented and compared to literature data. The incremental volume of the orthoborate (BO3)3− anion has been determined and is compared to the Biltz volume

Molecular and crystal structure of a copper(II) complex of sildenafil

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Akhmatkhodja N. Yunuskhodjayev ◽  
Shokhista F. Iskandarova ◽  
Vahobjon Kh. Sabirov
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Unit Cell ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
Piperazine Ring ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters

Abstract The crystal structure of a copper(II) complex of protonated sildenafil, CuCl3C22H31N6O4S⋅2H2O was studied by single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P21/n with the unit cell parameters a = 15.4292(2), b = 9.06735(12), c = 21.1752(2) Å, V = 2945.48(7) Å3, Z = 4. The Cu atom is coordinated by the sildenafil ligand via the N2 atom of the pyrazolopyrimidine ring and by three chloride anions. Sildenafil is protonated at the methylated N6 atom of the piperazine ring and it is cation ligand with a 1+ charge.

An explanation for the origin of hemihedrism in wulfenite: the single-crystal structures of I4̄1/a and I4̄ tungstenian wulfenites

2000 ◽  
Vol 64 (6) ◽  
pp. 1057-1062 ◽  
Author(s):  
D. E. Hibbs ◽  
C. M. Jury ◽  
P. Leverett ◽  
I. R. Plimer ◽  
P. A. Williams
Keyword(s):  
Single Crystal ◽  
Crystal Structures ◽  
San Francisco ◽  
Analytical Data ◽  
Site Occupancy ◽  
Unit Cell ◽  
Special Position ◽  
Space Group ◽  
X Ray ◽  
Single Crystal Structures

AbstractThe single-crystal X-ray structure of tungstenian wulfenite-I41/a containing 10 mol.% WO3 from the San Francisco mine, Sonora, Mexico, space group I41/a, a = 5.436(2), c = 12.068(8)Å and Z = 4, has been refined to R = 0.052. The Mo and W are disordered over special position 4a (0,0,0) in the lattice. Tungstenian wulfenite-I4̄ (‘chillagite’) from the Christmas Gift mine, Chillagoe, Queensland, Australia (Museum of Victoria specimen M16934), crystallizes in the closely related tetragonal space group I4̄, with a = 5.441(1), c = 12.068(6) Å and Z = 4. The structure was refined to R = 0.038. Refined site occupancy factors show that Mo and W are not distributed equally over the two crystallographically independent Mo/W positions, being 0.136(2) for Mo and 0.114(2) for W in special position 2a (0,0,0) and 0.184(2) for Mo and 0.066(2) for W in special position 2c (0,Ý,Ü). These give a composition corresponding to wulfenite64stolzite36, in agreement with analytical data. The Mo/W distributions in the unit cell provide one explanation for the origin of hemihedrism in the wulfenite-stolzite series.

THE CRYSTAL STRUCTURE OF Bi2Te2Se

1961 ◽  
Vol 39 (7) ◽  
pp. 1040-1043 ◽  
Author(s):  
J. A. Bland ◽  
S. J. Basinski
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Unit Cell ◽  
Hexagonal Cell ◽  
Space Group ◽  
X Ray ◽  
Contact Distance

The crystal structure of Bi2Te2Se has been determined by X-ray single crystal methods. The unit cell is trigonal, space group [Formula: see text] with hexagonal cell edges a = 4.28 ± 0.02 Å, c = 29.86 ± 0.10 Å, and there are three formula units per unit cell. The structure is of the C33 type and a comparison is made with other C33 structures, Bi2Se3, Bi2Te3, and Bi2Te2S. An important common feature of these compounds is that the atom on the center of symmetry has a relatively large contact distance with each of its six Bi neighbors.

Reactions between Co(II), 1,2-bis(diphenylphosphino)ethane, and NaBH3CN in the presence and absence of CO. The crystal structure of bis(cyanotrihydroborato)tetrakis(N,N-dimethylformamide)cobalt(II)

1988 ◽  
Vol 66 (7) ◽  
pp. 1770-1775 ◽  
Author(s):  
David J. Elliot ◽  
Sanna Haukilahti ◽  
David G. Holah ◽  
Alan N. Hughes ◽  
Stanislaw Maciaszek ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Unit Cell ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
Triclinic Space Group ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters ◽  
R Factor

Reactions between Co(II), Diphos, and NaBH3CN lead to Co(BH3CN)2(Diphos)2, 1, or [Co(BH3CN)(Diphos)2]X, 2 (X = ClO4 or BPh4), and, in certain solvents, 2 reacts to produce [Co(CN)(Diphos)2](ClO4). Compound 1 can be reversibly converted to Co(BH3CN)2(DMF)4, 4, via Co(BH3CN)2(Diphos)(DMF). In addition, 1 reacts with CO to form the Co(I) and Co(III) compounds [Co(Diphos)2](CO)]X and [Co(Diphos)2(CN)2]X (X = BH3CN or BPh4). Single crystal X-ray diffraction studies of 4 show that the compound crystallizes in the triclinic space group [Formula: see text], with unit cell parameters a = 7.572(6), b = 9.695(6), c = 9.395(6) Å, α = 81.06(4), β = 68.46(5), γ = 68.19(5)°, V = 595.5 Å3, Z = 1, and dcalcd = 1.202 g cm−3. The structure converged to a conventional R factor of 0.040 for 2841 observations and showed an octahedral arrangement of four O atoms from DMF molecules and two trans N-bound BH3CN groups around the Co(II) center.

scholarly journals Symmetry-extended counting rules for periodic frameworks

2014 ◽  
Vol 372 (2008) ◽  
pp. 20120029 ◽  
Author(s):  
S. D. Guest ◽  
P. W. Fowler
Keyword(s):  
Point Group ◽  
Factor Group ◽  
Unit Cell ◽  
Group Symmetry ◽  
Point Group Symmetry ◽  
Space Group ◽  
Counting Rules ◽  
Periodic Frameworks ◽  
Explicit Expressions

A symmetry-adapted version of the Maxwell rule appropriate to periodic bar-and-joint frameworks is obtained, and is further extended to body-and-joint systems. The treatment deals with bodies and forces that are replicated in every unit cell, and uses the point group isomorphic to the factor group of the space group of the framework. Explicit expressions are found for the numbers and symmetries of detectable mechanisms and states of self-stress in terms of the numbers and symmetries of framework components. This approach allows detection and characterization of mechanisms and states of self-stress in microscopic and macroscopic materials and meta-materials. Illustrative examples are described. The notion of local isostaticity of periodic frameworks is extended to include point-group symmetry.

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