Structural Science

 

Acta Cryst. (2001). B57, 1-12  [ doi:10.1107/S0108768100017638 ]

Synthons and design in metal phosphates and oxalates with open architectures

C. N. R. Rao, S. Natarajan, A. Choudhury, S. Neeraj and R. Vaidhyanathan

Synopsis: The fascinating three-dimensional architectures of metal phosphates and related materials are shown to be formed by a progressive building-up process, starting from low-dimensional structures. Accordingly, the zero- and one-dimensional structures act as synthons in the formation of these structures.

Online February 2001

 

Acta Cryst. (2001). B57, 13-19  [ doi:10.1107/S0108768100013203 ]

Structure of Nd₁₀W₂₂O₈₁ from high-resolution electron microscopy and X-ray powder diffraction

C. Grenthe, A. A. Guagliardi, M. Sundberg and P.-E. Werner

Synopsis: The crystal structure of Nd₁₀W₂₂O₈₁ has been determined, using a combination of high-resolution transmission electron microscopy and X-ray powder diffraction methods. Nd₁₀W₂₂O₈₁ is a new type of pentagonal column (PC) structure.

Online February 2001

 

Acta Cryst. (2001). B57, 20-26  [ doi:10.1107/S0108768100013215 ]

High-pressure structures of - and -ZrMo₂O₈

A. M. Krogh Andersen and S. Carlson

Synopsis: The structure of the monoclinic high-pressure phase -ZrMo₂O₈ has been solved by direct methods and refined using high-pressure synchrotron X-ray powder diffraction data. Rietveld refinements of the - and -phase from 0.2 to 1.9  GPa have been performed.

Online February 2001

 

Acta Cryst. (2001). B57, 27-35  [ doi:10.1107/S0108768100014506 ]

Kinetic behaviour investigations and crystal structure of nitric acid dihydrate

N. Lebrun, F. Mahe, J. Lamiot, M. Foulon, J. C. Petit and D. Prevost

Synopsis: The kinetic behaviour of nitric acid dihydrate, HNO₃·2H₂O, proves its possible crystallization. From a single crystal the molecular and crystal structures have been determined, revealing a two-dimensional hydrogen-bond network, and molecular arrangement intermediate between those of the monohydrate and the trihydrate of nitric acid.

Online February 2001

 

Acta Cryst. (2001). B57, 36-44  [ doi:10.1107/S0108768100014695 ]

Structure of manganese diacetate tetrahydrate and low-temperature methyl-group dynamics

B. Nicolaï, G. J. Kearley, A. Cousson, W. Paulus, F. Fillaux, F. Gentner, L. Schröder and D. Watkin

Synopsis: The crystal structure of manganese diacetate tetrahydrate has been determined by single-crystal neutron diffraction. A quantum model is proposed to account for the observed proton density distributions and the rotational dynamics of methyl groups observed by inelastic neutron scattering.

Online February 2001

 

Acta Cryst. (2001). B57, 45-53  [ doi:10.1107/S0108768100013896 ]

Structures of three cis-₁ and three cis-₂ isomers of [Co(trien)(aminoacidato)]²⁺ complexes

J. Cai, X. Hu, X. Feng, L. Ji and I. Bernal

Synopsis: The crystal structures and absolute configurations of three cis-₁ and three cis-₂ isomers of [Co(trien)(L-aminoacidato)]²⁺ are reported, as are their crystallization behavior and packing features.

Online February 2001

 

Acta Cryst. (2001). B57, 54-62  [ doi:10.1107/S0108768100013197 ]

X-ray investigations of sulfur-containing fungicides. II. Intramolecular forces governing the conformation of four novel -phenylazo- and -phenylhydrazono--ketosulfones

W. M. Wolf

Synopsis: The title compounds represent a new group of fungicides characterized by substantial photodynamic activity. Their conformation is controlled by stereoelectronic interactions which help to reduce the large electron-withdrawing capacity of the sulfonyl group. Additionally, strong intramolecular resonance-assisted hydrogen bonds between the sulfonyl and -phenylhydrazono groups exist in two of the compounds investigated. The strength of these bonds and the stereoelectronic back-donation are mutually related.

Online February 2001

 

Acta Cryst. (2001). B57, 63-71  [ doi:10.1107/S0108768100013331 ]

Synthesis and structure of, and bonding in some derivatives of 2,6,9,10-tetraoxatricyclo[3.3.1.1^3,8]decane

J. Simons, H. G. Thomas, S. R. Hall and G. Raabe

Synopsis: The structures of five members of a new class of compounds have been determined by X-ray diffraction. Comparison of the measured bond lengths with their quantum chemically calculated counterparts might lead to erroneous conclusions if correlation energy is omitted from the calculations.

Online February 2001

 

Acta Cryst. (2001). B57, 72-81  [ doi:10.1107/S0108768100013975 ]

Structural studies on C-amidated amino acids and peptides: structures of hydrochloride salts of C-amidated Ile, Val, Thr, Ser, Met, Trp, Gln and Arg, and comparison with their C-unamidated counterparts

Y. In, M. Fujii, Y. Sasada and T. Ishida

Synopsis: To elucidate the structural features caused by C-amidation of amino acids, the crystal structures of HCl salts of C-amidated Ile, Val, Thr, Ser, Met, Trp, Gln and Arg have been analysed and compared with those of the corresponding amino acids. The C-HO hydrogen bonds, intermolecular carbonyl-carbonyl interactions and the interaction patterns with Cl ions could be considered as structural features which differentiate both molecules from each other.

Online February 2001

 

Acta Cryst. (2001). B57, 82-87  [ doi:10.1107/S0108768100014087 ]

Structures of tetrathiabenzoquinone derivatives and the order-disorder phase transition

S. Matsumoto and J. Mizuguchi

Synopsis: The crystal structures of two tetrathiabenzoquinone derivatives were found to form characteristic one-dimensional molecular columns and two-dimensional or quasi two-dimensional molecular sheets.

Online February 2001

 

Acta Cryst. (2001). B57, 88-94  [ doi:10.1107/S010876810001380X ]

Automatic detection of molecular symmetry in the Cambridge Structural Database

J. C. Cole, J. W. Yao, G. P. Shields, W. D. S. Motherwell, F. H. Allen and J. A. K. Howard

Synopsis: A program to detect molecular symmetry in selected crystal structures from the Cambridge Structural Database is reported, plus an implementation of the display of symmetry elements.

Online February 2001

 

Acta Cryst. (2001). B57, 95-102  [ doi:10.1107/S0108768100014841 ]

Ethane-1,2-diphosphonic acid as a building block in supramolecular chemistry; a pillared-layer framework and framework-encapsulated cations

P. S. Wheatley, A. J. Lough, G. Ferguson, C. J. Burchell and C. Glidewell

Synopsis: Organic salts formed between ethane-1,2-diphosphonic acid and the diamines piperazine and 4,4'-trimethylenedipiperidine are both characterized by richly complex intermolecular hydrogen bonding, giving two different three-dimensional framework structures.

Online February 2001

 

Acta Cryst. (2001). B57, 103-106  [ doi:10.1107/S0108768100014348 ]

Competition of hydrogen-bond acceptors for the strong carboxyl donor

T. Steiner

Synopsis: Database study on the competitive effects involving the carboxyl group. A correlation between the success in competition and the average hydrogen-bond distance is established.

Online February 2001

 

Acta Cryst. (2001). B57, 107-111  [ doi:10.1107/S0108768100016335 ]

Notes for Authors

Online February 2001

 

Acta Cryst. (2001). B57, 112  [ doi:10.1107/S0108768100019881 ]

Modern crystallography Vol. 2. Structure of Crystals.

Online February 2001