ChemInform Abstract: Synthesis and Crystal Structure of α-Ba2ZrF8 and Pb2ZrF8 Determined ab initio from Synchrotron and Neutron Powder Diffraction Data.

ChemInform ◽  
2010 ◽  
Vol 29 (39) ◽  
pp. no-no
Author(s):  
A. LE BAIL ◽  
J.-P. LAVAL
Keyword(s):  
Crystal Structure ◽  
Ab Initio ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Neutron Powder Diffraction ◽  
Powder Diffraction Data ◽  
Synthesis And Crystal Structure ◽  
Neutron Powder Diffraction Data

Synthesis and crystal structure of the pyrovanadate Na2ZnV2O7

2005 ◽  
Vol 20 (3) ◽  
pp. 189-192 ◽  
Author(s):  
Alexander P. Tyutyunnik ◽  
Vladimir G. Zubkov ◽  
Ludmila L. Surat ◽  
Boris V. Slobodin ◽  
Gunnar Svensson
Keyword(s):  
Crystal Structure ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Neutron Powder Diffraction ◽  
Type Structure ◽  
Powder Diffraction Data ◽  
Synthesis And Crystal Structure ◽  
X Ray ◽  
Neutron Powder Diffraction Data ◽  
Tetragonal Unit Cell

The compound Na2ZnV2O7 with an åkermanite-type structure has been synthesized. It has a tetragonal unit cell, a=8.2711(4), c=5.1132(2) Å, and crystallizes with P-421m symmetry, Z=2. Its crystal structure has been refined from a combination of X-ray and neutron powder diffraction data. The structure contains layers of corner-sharing VO4 and ZnO4 tetrahedra, the former in pairs forming pyrovanadate V2O7 units. The sodium atoms are positioned between the layers, with a distorted antiprismatic coordination of oxygen atoms.

Synthesis and crystal structure determination of 6-phenyl-5-phenylsulfonyl-1,2,3,4-tetrahydropyrimidine-2-thione from neutron powder diffraction data

2001 ◽  
Vol 216 (12) ◽  
Author(s):  
V. Rybakov ◽  
V. V. Chernyshev ◽  
V. A. Tafeenko ◽  
A. D. Shutalev ◽  
A. I. Kurbakov ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Structure Determination ◽  
Title Compound ◽  
Neutron Powder Diffraction ◽  
Powder Diffraction Data ◽  
Synthesis And Crystal Structure ◽  
Neutron Powder Diffraction Data

AbstractThe title compound was synthesized by reaction of N-(azidomethyl)thiourea or N-(tosylmethyl)thiourea with

The crystal structure of perdeuterated methanol monoammoniate (CD3OD·ND3) determined from neutron powder diffraction data at 4.2 and 180 K

2009 ◽  
Vol 42 (6) ◽  
pp. 1054-1061 ◽  
Author(s):  
A. D. Fortes ◽  
I. G. Wood ◽  
K. S. Knight
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Rietveld Method ◽  
Neutron Powder Diffraction ◽  
Relative Volume ◽  
Powder Diffraction Data ◽  
Orthorhombic Space Group ◽  
Neutron Powder Diffraction Data

The crystal structure of perdeuterated methanol monoammoniate, CD3OD·ND3, has been solved from neutron powder diffraction data collected at 4.2 and 180 K. The crystal structure is orthorhombic, space groupPbca(Z= 8), with unit-cell dimensionsa= 11.02320 (7),b= 7.66074 (6),c= 7.59129 (6) Å,V= 641.053 (5) Å3[ρcalc= 1162.782 (9) kg m−3] at 4.2 K, anda= 11.21169 (5),b= 7.74663 (4),c= 7.68077 (5) Å,V= 667.097 (4) Å3[ρcalc= 1117.386 (7) kg m−3] at 180 K. The crystal structure was determined byab initiomethods from the powder data; atomic coordinates and anisotropic displacement parameters were subsequently refined by the Rietveld method toRp< 3% at both temperatures. The crystal comprises a sheet-like structure in thebccrystallographic plane, consisting of strongly hydrogen bonded elements; these sheets are stacked along theaaxis, and adjacent sheets are linked by what may be comparatively weak C—D...O hydrogen bonds. Within the strongly bonded sheet structure, ND3molecules are tetrahedrally coordinated by the hydroxy moieties of the methanol molecule, accepting one hydrogen bond (O—D...N) of length ∼1.75 Å, and donating three hydrogen bonds (N—D...O) of length 2.15–2.25 Å. Two of the methyl deuterons appear to participate in weak interlayer hydrogen bonds (C—D...O) of length 2.7–2.8 Å. The hydrogen bonds are ordered at both 4.2 and 180 K. The relative volume change on warming from 4.2 to 180 K, ΔV/V, is +4.06%, which is comparable to, but more nearly isotropic (as determined from the relative change in axial lengths,e.g.Δa/a) than, that observed in deuterated methanol monohydrate.

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