High‐pressure structural properties of naphthalene up to 6 GPa. (1st June 2014)

• Record Type: Journal Article
• Authors: Likhacheva, Anna Y.; Rashchenko, Sergey V.; Litasov, Konstantin D.
• Is Part Of: Journal of applied crystallography. Volume 47:Part 3(2014:Jun.)
• Page Start: 984
• Page End: 991
• Publication Date: 2014-06-01
• Subjects: Crystallography -- Periodicals; 548.05
• DOI: 10.1107/S1600576714005937
• Languages: English
• ISSNs: 0021-8898

Abstract

<abstract abstract-type="main" xml:lang="en"> <title> <x xml:space="preserve">Abstract</x> </title> <p>The elastic and structure behavior of solid naphthalene (C<sub>10</sub>H<sub>8</sub>) was studied by <italic>in situ</italic> synchrotron powder X‐ray diffraction up to 5.6 GPa in a diamond anvil cell. Rietveld refinements were applied to obtain atomic coordinates and lattice parameters as a function of pressure. Within the studied pressure range, the intramolecular C—C and C—H distances decrease by 3.5%, whereas intermolecular distances within and between the herringbone layers decrease by 18 and 10%, respectively. Noindication of a symmetry change (space group <italic>P</italic>2<sub>1</sub>/<italic>a</italic>) was observed. A markedly anisotropic compression is preserved up to 5.6 GPa, with linear compressibilities β<italic><sub>a</sub></italic>:β<italic><sub>b</sub></italic>:β<italic><sub>c</sub></italic>:β<sub>[200]</sub>≃ 7:5:3:10. Fitting of the <italic>P</italic>–<italic>V</italic> experimental data to the Vinet equation of state yields <italic>K</italic><sub>0</sub> = 7.9 (3) GPa and <italic>K</italic>′ = 7.5 (3) at <italic>V</italic><sub>0</sub> = 361 Å<sup>3</sup>. At the highest pressure of 5.6 GPa, the unit‐cell volume is decreased by 23%. The overall regularity of compression confirms the absence of major structural transformations in naphthalene up to 5.6 GPa. However, a distinct bend of the pressure dependence of the interlayer C...C distances observed at 2 GPa suggests a minor structural irregularity, which is apparently associated with spectroscopic anomalies observed previously.</p> </abstract>