Unit cell constants of zeolites stabilized by dealumination determination of Al content from lattice parameters

AbstractN-M ethyl-2-dimethylaluminium pyrrolide, (CH3)2Al -C4H3NCH3, crystallizes in the triclinic space group P1̄ with the lattice constants a = 700.5(1), b = 725.9(1), c = 886.8(1) pm, α = 67.69(1)°, β = 70.99(1)°, γ = 88.48(1)°, and Z = 2. This compound is isotypic with the gallium homologue [1], the shortest metal-ring contact between the two molecules of one unit cell decreases to 228.6 pm. N-dimethylgallium tetramethylpyrrolide has been synthesized from Li-N (CCH3)4 and (CH3)2GaCl. This “π-associate” crystallizes in the monoclinic space group P21/c with the lattice parameters a = 989.9(2), b = 1305.4(3), c = 878.3(2) pm, β - 112.73(1)° and 4 units per cell. Again two centrosymmetrically orientated molecules form a dimer by short (224.0 pm) intermolecular “Ga - πC ” contacts but the structure differs significant from the structure of the indium homologue [1].

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Determination of the structure of bis(propyldithiocarbamate)nickel(II)

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19901010 ◽

1990 ◽

Vol 55 (4) ◽

pp. 1010-1014 ◽

Cited By ~ 1

Author(s):

Jiří Kameníček ◽

Richard Pastorek ◽

František Březina ◽

Bohumil Kratochvíl ◽

Zdeněk Trávníček

Keyword(s):

Molecular Structure ◽

Title Compound ◽

Crystal And Molecular Structure ◽

Heavy Atom ◽

Unit Cell ◽

Monoclinic Space Group ◽

Planar Configuration ◽

Compound C ◽

Heavy Atom Method

The crystal and molecular structure of the title compound (C8H16N2NiS4) was solved by the heavy atom method and the structure was refined anisotropically to a final R factor of R = 0.029 (wR = 0.037) for 715 observed reflections. The crystal is monoclinic, space group P21/c with a = 948.3(2), b = 776.9(2), c = 1 167.4(2) pm, β = 125.14(2)°, Z = 2. The molecule contains two four-membered NiSCS rings of approximately planar configuration with the Ni atom situated at a centre of symmetry. The molecules are arranged in chains along the c-axis of the unit cell.

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Correction “Density Functional Theory and Experimental Determination of Band Gaps and Lattice Parameters in Kesterite Cu2ZnSn(SxSe1–x)4”

The Journal of Physical Chemistry Letters ◽

10.1021/acs.jpclett.0c03723 ◽

2020 ◽

pp. 612-612

Author(s):

Chuan-Jia Tong ◽

Holly J. Edwards ◽

Theodore D. C. Hobson ◽

Oliver S. Hutter ◽

Ken Durose ◽

...

Keyword(s):

Density Functional Theory ◽

Experimental Determination ◽

Density Functional ◽

Lattice Parameters ◽

Band Gaps ◽

Functional Theory

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Indexing approximants of icosahedral quasicrystals

Acta Crystallographica Section A Foundations of Crystallography ◽

10.1107/s0108767399006224 ◽

1999 ◽

Vol 55 (6) ◽

pp. 975-983 ◽

Cited By ~ 3

Author(s):

M. Quiquandon ◽

A. Katz ◽

F. Puyraimond ◽

D. Gratias

Keyword(s):

Unit Cell ◽

Dimensional Lattice ◽

Geometrical Properties ◽

Actual Model ◽

Icosahedral Quasicrystals ◽

Low Dimensional

It is well known that the crystallography of approximants is directly related to that of the parent quasicrystal, once its unit-cell vectors are identified as parallel projections of certain N-dimensional lattice nodes {\bf A}^{i}. Derived here are explicit simple relations for calculating the shear matrices {\boldvarepsilon} and the related crystallographic properties of the corresponding approximants, including diffraction indexing and the determination of the lattice in perpendicular space. Applied to low-dimensional approximants, the derivation shows that the systematic `accidental' extinction rules observed in the pentagonal phases are generic extinctions that are due to the geometrical properties of the projected 1D lattice and are independent of the actual model of the quasicrystal.

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