Neutron diffraction, synchrotron radiation and EXAFS spectroscopy study of crystal structure peculiarities of the lanthanum nickelates Lan+1NinOy (n=1,2,3) / Voronin VI,Berger IF,Cherepanov VA,Gavrilova LY,Petrov AN,Ancharov AI,Tolochko BP,Nikitenko SG // NUCLEAR INSTRUMENTS \& METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT. - 2001. - V. 470, l. 1-2. - P. 202-209.

ISSN/EISSN:

0168-9002 / нет данных

Type:

Article; Proceedings Paper

Abstract:

Complex oxides: La2NiO4 (I), La3Ni2O7 (II) and La4Ni3O10 (III), belonging to the homologous series Lan+1MenO3n+1, were prepared by the traditional ceramic technique (I) and by that of citrate or nitrate precursors (II), (III). The crystal structure of all samples was determined by means of X-ray diffraction, neutron diffraction and synchrotron radiation spectroscopy. Data on nickel coordination were obtained by EXAFS spectroscopy. Phases (II) and (III) were used for structural investigations as prepared powders (quenched from 1100 C in air), phase (I) was pressed into rectangular bars (5 x 5 x 30 mm) and sintered at 1370 degreesC for 5 h, Structural parameters of all phases were refined based on Cmca (I), Cmcm (II) and Cmca (III) space group using the Rietveld analysis. Bond lengths in all compounds were calculated. Oxygen octahedrons centered by nickel ions were distorted in (I) and (II). (I) has two and (II) has four different Ni-O interatomic distances. Phase (III) has both ideal and distorted octahedrons in the structure and two types of nonequivalent Ni sites, as a result. The oxidation state of cations was estimated using the average cation-anion distance approach and the so-called bond valence approach. The results allowed us to suggest that Ni3+ preferably occupied the Nil sites, i.e. it is possible to assume some charge ordering inside the lattice. (C) 2001 Elsevier Science B.V. All rights reserved.

Author keywords:

lanthanum nickelates; crystal structure; EXAFS; neutron diffraction NI-O; PR; ND; SUPERCONDUCTIVITY; LA3NI2O7-DELTA; STABILITY; LA2NIO4; SYSTEM; LN=LA; MN

DOI:

10.1016/S0168-9002(01)01036-1

Web of Science ID:

ISI:000170979000042

Соавторы в МНС:

Другие поля

Поле	Значение
Month	SEP 1
Note	13th Conference on National Synchrotron Radiation, NOVOSIBIRSK, RUSSIA, JUL 17-21, 2000
Publisher	ELSEVIER SCIENCE BV
Address	PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
Language	English
Keywords-Plus	NI-O; PR; ND; SUPERCONDUCTIVITY; LA3NI2O7-DELTA; STABILITY; LA2NIO4; SYSTEM; LN=LA; MN
Research-Areas	Instruments \& Instrumentation; Nuclear Science \& Technology; Physics
Web-of-Science-Categories	Instruments \& Instrumentation; Nuclear Science \& Technology; Physics, Nuclear; Physics, Particles \& Fields
ResearcherID-Numbers	Cherepanov, Vladimir/E-6451-2014 Voronin, Vladimir/J-7733-2013
ORCID-Numbers	Cherepanov, Vladimir/0000-0003-3653-6459 Voronin, Vladimir/0000-0002-3901-9812
Number-of-Cited-References	28
Usage-Count-Last-180-days	1
Usage-Count-Since-2013	14
Journal-ISO	Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip.
Doc-Delivery-Number	472HX