Incommensurately modulated structure of morpholinium tetrafluoroborate and configurational versus chemical entropies at the incommensurate and lock-in phase transitions

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378271%3A_____%2F17%3A00479715" target="_blank" >RIV/68378271:_____/17:00479715 - isvavai.cz</a>

Result on the web

<a href="http://dx.doi.org/10.1107/S2052520617009398" target="_blank" >http://dx.doi.org/10.1107/S2052520617009398</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1107/S2052520617009398" target="_blank" >10.1107/S2052520617009398</a>

Result language

angličtina

Original language name

Incommensurately modulated structure of morpholinium tetrafluoroborate and configurational versus chemical entropies at the incommensurate and lock-in phase transitions

Original language description

Morpholinium tetrafluoroborate belongs to a class of ferroelectric compounds ABX4. However, it does not develop ferroelectric properties because the incommensurate phase below Tc,I = 153 K is centrosymmetric, the threefold superstructure below Tc,II = 117–118 K possesses the acentric but non-ferroelectric space group P212121. A structure model for the incommensurately modulated phase is reported. A mechanism is proposed for the phase transitions, whereby at low temperatures morpholinium cations are shaped around the tetrafluoroborate anion in order to optimize the interactions with one orientation of this anion and, thus, forcing [BF4] anions into this orientation.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10302 - Condensed matter physics (including formerly solid state physics, supercond.)

Project

<a href="/en/project/GA15-12653S" target="_blank" >GA15-12653S: Validation and Interpretation of Modulated Structures</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2017

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Acta Crystallographica. Section B: Structural Science, Crystal Engineering and Materials

ISSN

2052-5206

e-ISSN

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Volume of the periodical

73

Issue of the periodical within the volume

Jun

Country of publishing house

GB - UNITED KINGDOM

Number of pages

8

Pages from-to

836-843

UT code for WoS article

000412273900008

EID of the result in the Scopus database

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