|
Records |
Links |
|
Author |
Rozova, M.G.; Grigoriev, V.V.; Bobrikov, I.A.; Filimonov, D.S.; Zakharov, K.V.; Volkova, O.S.; Vasiliev, A.N.; Antipov, E.V.; Tsirlin, A.A.; Abakumov, A.M. |
|
|
Title |
Synthesis, structure and magnetic ordering of the mullite-type Bi2Fe4-xCrxO9 solid solutions with a frustrated pentagonal Cairo lattice |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
Dalton T |
|
|
Volume |
45 |
Issue |
45 |
Pages |
1192-1200 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
Highly homogeneous mullite-type solid solutions Bi2Fe4-xCrxO9 (x = 0.5, 1, 1.2) were synthesized using a soft chemistry technique followed by a solid-state reaction in Ar. The crystal structure of Bi2Fe3CrO9 was investigated using X-ray and neutron powder diffraction, transmission electron microscopy and Fe-57 Mossbauer spectroscopy (S.G. Pbam, a = 7.95579(9) angstrom , b = 8.39145(9) angstrom, c = 5.98242(7) angstrom, R-F(X-ray) = 0.022, R-F(neutron) = 0.057). The ab planes in the structure are tessellated with distorted pentagonal loops built up by three tetrahedrally coordinated Fe sites and two octahedrally coordinated Fe/Cr sites, linked together in the ab plane by corner-sharing forming a pentagonal Cairo lattice. Magnetic susceptibility measurements and powder neutron diffraction show that the compounds order antiferromagnetically (AFM) with the Neel temperatures decreasing upon increasing the Cr content from T-N similar to 250 K for x = 0 to T-N similar to 155 K for x = 1.2. The magnetic structure of Bi2Fe3CrO9 at T = 30 K is characterized by a propagation vector k = (1/2,1/2,1/2). The tetrahedrally coordinated Fe cations form singlet pairs within dimers of corner-sharing tetrahedra, but spins on the neighboring dimers are nearly orthogonal. The octahedrally coordinated (Fe, Cr) cations form antiferromagnetic up-up-down-down chains along c, while the spin arrangement in the ab plane is nearly orthogonal between nearest neighbors and collinear between second neighbors. The resulting magnetic structure is remarkably different from the one in pure Bi2Fe4O9 and features several types of spin correlations even on crystallographically equivalent exchange that may be caused by the simultaneous presence of Fe and Cr on the octahedral site. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
London |
Editor |
|
|
|
Language |
|
Wos |
000367614700041 |
Publication Date |
2015-11-30 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0300-9246; 1477-9226; 1472-7773 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.029 |
Times cited |
|
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: NA |
|
|
Call Number |
UA @ lucian @ c:irua:131095 |
Serial |
4257 |
|
Permanent link to this record |
|
|
|
|
Author |
Rozova, M.G.; Grigoriev, V.V.; Tyablikov, O.A.; Filimonov, D.S.; Zakharov, K.V.; Volkova, O.S.; Vasiliev, A.N.; Antipov, E.V.; Abakumov, A.M. |
|
|
Title |
Doping of Bi4Fe5O13F with pentagonal Cairo lattice with Cr and Mn: Synthesis, structure and magnetic properties |
Type |
A1 Journal article |
|
Year |
2017 |
Publication |
Materials research bulletin |
Abbreviated Journal |
Mater Res Bull |
|
|
Volume |
87 |
Issue |
87 |
Pages |
54-60 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
The substitution of Cr3+ and Mn3+ for Fe3+ in the Bi4Fe6O13F oxyfluoride featuring the magnetically frustrated pentagonal Cairo lattice is reported. Bi4Fe4.1Cr0.9O13F and BiFe4.2Mn0.8O13F have been prepared using a solid state reaction in inert atmosphere. Their crystal structures were studied with transmission electron microscopy, powder X-ray diffraction and Fe-57 Mossbauer spectroscopy (S.G. P4(2)/mbc, a = 8.27836(2)angstrom, c = 18.00330(9) angstrom, R-F = 0.031 (Bi4Fe4.1Cr0.9O13F)), a= 8.29535(3)angstrom, c= 18.0060(1)angstrom, R-F = 0.027 (Bi4Fe4.1Cr0.9O13F)). The structures are formed by infinite rutile-like chains of the edge sharing BO6 octahedra (B transition metal cations) linked by the Fe2O7 groups of two corner-sharing tetrahedra. The"voids in thus formed framework are occupied by the Bi4F tetrahedra. The Fe-57 Mossbauer spectroscopy reveals that Cr3+ and Mn3+ replace Fe3+. exclusively at the octahedral positions. The Mn- and Cr-doped compounds demonstrate antiferromagnetic ordering below T-N =165 K and 120 K, respectively. (C) 2016 Elsevier Ltd. All rights reserved. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
|
|
Language |
|
Wos |
000392681800009 |
Publication Date |
2016-11-17 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0025-5408 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.446 |
Times cited |
1 |
Open Access |
Not_Open_Access |
|
|
Notes |
; The work has been supported by the Russian Science Foundation (grant 14-13-00680). ; |
Approved |
Most recent IF: 2.446 |
|
|
Call Number |
UA @ lucian @ c:irua:141535 |
Serial |
4498 |
|
Permanent link to this record |
|
|
|
|
Author |
Batuk, M.; Batuk, D.; Tsirlin, A.A.; Rozova, M.G.; Antipov, E.V.; Hadermann, J.; Van Tendeloo, G. |
|
|
Title |
Homologous series of layered perovskites An+1BnO3n-1Cl : crystal and magnetic structure of a new oxychloride Pb4BiFe4O11Cl |
Type |
A1 Journal article |
|
Year |
2013 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
|
|
Volume |
52 |
Issue |
4 |
Pages |
2208-2218 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
The nuclear and magnetic structure of a novel oxychloride Pb4BiFe4O11Cl has been studied over the temperature range 1.5700 K using a combination of transmission electron microscopy and synchrotron and neutron powder diffraction [space group P4/mbm, a = 5.5311(1) Å, c = 19.586(1) Å, T = 300 K]. Pb4BiFe4O11Cl is built of truncated (Pb,Bi)3Fe4O11 quadruple perovskite blocks separated by CsCl-type (Pb,Bi)2Cl slabs. The perovskite blocks consist of two layers of FeO6 octahedra located between two layers of FeO5 tetragonal pyramids. The FeO6 octahedra rotate about the c axis, resulting in a √2ap × √2ap × c superstructure. Below TN = 595(17) K, Pb4BiFe4O11Cl adopts a G-type antiferromagnetic structure with the iron magnetic moments confined to the ab plane. The ordered magnetic moments at 1.5 K are 3.93(3) and 3.62(4) μB on the octahedral and square-pyramidal iron sites, respectively. Pb4BiFe4O11Cl can be considered a member of the perovskite-based An+1BnO3n1Cl homologous series (A = Pb/Bi; B = Fe) with n = 4. The formation of a subsequent member of the series with n = 5 is also demonstrated. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Easton, Pa |
Editor |
|
|
|
Language |
|
Wos |
000315255200067 |
Publication Date |
2013-02-05 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.857 |
Times cited |
6 |
Open Access |
|
|
|
Notes |
Countatoms |
Approved |
Most recent IF: 4.857; 2013 IF: 4.794 |
|
|
Call Number |
UA @ lucian @ c:irua:106185 |
Serial |
1486 |
|
Permanent link to this record |
|
|
|
|
Author |
Abakumov, A.M.; Batuk, M.; Tsirlin, A.A.; Tyablikov, O.A.; Sheptyakov, D.V.; Filimonov, D.S.; Pokholok, K.V.; Zhidal, V.S.; Rozova, M.G.; Antipov, E.V.; Hadermann, J.; Van Tendeloo, G.; |
|
|
Title |
Structural and magnetic phase transitions in the AnBnO3n-2 anion-deficient perovskites Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 |
Type |
A1 Journal article |
|
Year |
2013 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
|
|
Volume |
52 |
Issue |
14 |
Pages |
7834-7843 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
Novel anion-deficient perovskite-based ferrites Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 were synthesized by solid-state reaction in air. Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 belong to the perovskite-based AnBnO3n2 homologous series with n = 5 and 6, respectively, with a unit cell related to the perovskite subcell ap as ap√2 × ap × nap√2. Their structures are derived from the perovskite one by slicing it with 1/2[110]p(1̅01)p crystallographic shear (CS) planes. The CS operation results in (1̅01)p-shaped perovskite blocks with a thickness of (n 2) FeO6 octahedra connected to each other through double chains of edge-sharing FeO5 distorted tetragonal pyramids which can adopt two distinct mirror-related configurations. Ordering of chains with a different configuration provides an extra level of structure complexity. Above T ≈ 750 K for Pb2Ba2BiFe5O13 and T ≈ 400 K for Pb1.5Ba2.5Bi2Fe6O16 the chains have a disordered arrangement. On cooling, a second-order structural phase transition to the ordered state occurs in both compounds. Symmetry changes upon phase transition are analyzed using a combination of superspace crystallography and group theory approach. Correlations between the chain ordering pattern and octahedral tilting in the perovskite blocks are discussed. Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 undergo a transition into an antiferromagnetically (AFM) ordered state, which is characterized by a G-type AFM ordering of the Fe magnetic moments within the perovskite blocks. The AFM perovskite blocks are stacked along the CS planes producing alternating FM and AFM-aligned FeFe pairs. In spite of the apparent frustration of the magnetic coupling between the perovskite blocks, all n = 4, 5, 6 AnFenO3n2 (A = Pb, Bi, Ba) feature robust antiferromagnetism with similar Néel temperatures of 623632 K. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Easton, Pa |
Editor |
|
|
|
Language |
|
Wos |
000322087100006 |
Publication Date |
2013-02-13 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.857 |
Times cited |
10 |
Open Access |
|
|
|
Notes |
Countatoms |
Approved |
Most recent IF: 4.857; 2013 IF: 4.794 |
|
|
Call Number |
UA @ lucian @ c:irua:109213 |
Serial |
3196 |
|
Permanent link to this record |
|
|
|
|
Author |
Abakumov, A.M.; Hadermann, J.; Batuk, M.; d' Hondt, H.; Tyablikov, O.A.; Rozova, M.G.; Pokholok, K.V.; Filimonov, D.S.; Sheptyakov, D.V.; Tsirlin, A.A.; Niermann, D.; Hemberger, J.; Van Tendeloo, G.; Antipov, E.V. |
|
|
Title |
Slicing the Perovskite structure with crystallographic shear planes : the AnBnO3n-2 homologous series |
Type |
A1 Journal article |
|
Year |
2010 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
|
|
Volume |
49 |
Issue |
20 |
Pages |
9508-9516 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
A new AnBnO3n−2 homologous series of anion-deficient perovskites has been evidenced by preparation of the members with n = 5 (Pb2.9Ba2.1Fe4TiO13) and n = 6 (Pb3.8Bi0.2Ba2Fe4.2Ti1.8O16) in a single phase form. The crystal structures of these compounds were determined using a combination of transmission electron microscopy and X-ray and neutron powder diffraction (S.G. Ammm, a = 5.74313(7), b = 3.98402(4), c = 26.8378(4) Å, RI = 0.035, RP = 0.042 for Pb2.9Ba2.1Fe4TiO13 and S.G. Imma, a = 5.7199(1), b = 3.97066(7), c = 32.5245(8) Å, RI = 0.032, RP = 0.037 for Pb3.8Bi0.2Ba2Fe4.2Ti1.8O16). The crystal structures of the AnBnO3n−2 homologues are formed by slicing the perovskite structure with (01)p crystallographic shear (CS) planes. The shear planes remove a layer of oxygen atoms and displace the perovskite blocks with respect to each other by the 1/2[110]p vector. The CS planes introduce edge-sharing connections of the transition metal−oxygen polyhedra at the interface between the perovskite blocks. This results in intrinsically frustrated magnetic couplings between the perovskite blocks due to a competition of the exchange interactions between the edge- and the corner-sharing metal−oxygen polyhedra. Despite the magnetic frustration, neutron powder diffraction and Mssbauer spectroscopy reveal that Pb2.9Ba2.1Fe4TiO13 and Pb3.8Bi0.2Ba2Fe4.2Ti1.8O16 are antiferromagnetically ordered below TN = 407 and 343 K, respectively. The Pb2.9Ba2.1Fe4TiO13 and Pb3.8Bi0.2Ba2Fe4.2Ti1.8O16 compounds are in a paraelectric state in the 5−300 K temperature range. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Easton, Pa |
Editor |
|
|
|
Language |
|
Wos |
000282783400051 |
Publication Date |
2010-09-24 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.857 |
Times cited |
23 |
Open Access |
|
|
|
Notes |
Esteem 026019; Fwo |
Approved |
Most recent IF: 4.857; 2010 IF: 4.326 |
|
|
Call Number |
UA @ lucian @ c:irua:84963 |
Serial |
3041 |
|
Permanent link to this record |
|
|
|
|
Author |
Abakumov, A.M.; Rossell, M.D.; Seryakov, S.A.; Rozova, M.G.; Markina, M.M.; Van Tendeloo, G.; Antipov, E.V. |
|
|
Title |
Synthesis and crystal structure of novel CaRMnSnO6(R = La, Pr, Nd, Sm-Dy) double perovskites |
Type |
A1 Journal article |
|
Year |
2005 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
|
|
Volume |
15 |
Issue |
46 |
Pages |
4899-4905 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
|
|
Language |
|
Wos |
000233439300005 |
Publication Date |
2005-10-17 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0959-9428;1364-5501; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
|
Times cited |
8 |
Open Access |
|
|
|
Notes |
Iap V-1 |
Approved |
Most recent IF: NA |
|
|
Call Number |
UA @ lucian @ c:irua:56069 |
Serial |
3424 |
|
Permanent link to this record |
|
|
|
|
Author |
Hadermann, J.; Abakumov, A.M.; d' Hondt, H.; Kalyuzhnaya, A.S.; Rozova, M.G.; Markina, M.M.; Mikheev, M.G.; Tristan, N.; Klingeler, R.; Büchner, B.; Antipov, E.V. |
|
|
Title |
Synthesis and crystal structure of the Sr2Al1.07Mn0.93O5 brownmillerite |
Type |
A1 Journal article |
|
Year |
2007 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
|
|
Volume |
17 |
Issue |
7 |
Pages |
692-698 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
|
|
Language |
|
Wos |
000244085100016 |
Publication Date |
2006-12-15 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0959-9428;1364-5501; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
|
Times cited |
31 |
Open Access |
|
|
|
Notes |
Iap V-1 |
Approved |
Most recent IF: NA |
|
|
Call Number |
UA @ lucian @ c:irua:62061 |
Serial |
3430 |
|
Permanent link to this record |
|
|
|
|
Author |
Abakumov, A.M.; Rozova, M.G.; Antipov, E.V.; Hadermann, J.; Van Tendeloo, G.; Lobanov, M.V.; Greenblatt, M.; Croft, M.; Tsiper, E.V.; Llobet, A.; Lokshin, K.A.; Zhao, Y. |
|
|
Title |
Synthesis, cation ordering, and magnetic properties of the (Sb1-xPbx)2(Mn1-ySby)O4 solid solutions with the Sb2MnO4-type structure |
Type |
A1 Journal article |
|
Year |
2005 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
|
|
Volume |
17 |
Issue |
|
Pages |
1123-1134 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
|
|
Language |
|
Wos |
000227421300029 |
Publication Date |
2005-03-01 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
9.466 |
Times cited |
16 |
Open Access |
|
|
|
Notes |
Iap V-1 |
Approved |
Most recent IF: 9.466; 2005 IF: 4.818 |
|
|
Call Number |
UA @ lucian @ c:irua:51440 |
Serial |
3446 |
|
Permanent link to this record |
|
|
|
|
Author |
Abakumov, A.M.; Kalyuzhnaya, A.S.; Rozova, M.G.; Antipov, E.V.; Hadermann, J.; Van Tendeloo, G. |
|
|
Title |
Compositionally induced phase transition in the Ca2MnGa1-xAlxO5 solid solutions: ordering of tetrahedral chains in brownmillerite structure |
Type |
A1 Journal article |
|
Year |
2005 |
Publication |
Solid state sciences |
Abbreviated Journal |
Solid State Sci |
|
|
Volume |
7 |
Issue |
7 |
Pages |
801-811 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000230259500001 |
Publication Date |
2005-04-30 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1293-2558; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
1.811 |
Times cited |
38 |
Open Access |
|
|
|
Notes |
IAP V-1; RFBR 04-03-32785-a. |
Approved |
Most recent IF: 1.811; 2005 IF: 1.708 |
|
|
Call Number |
UA @ lucian @ c:irua:54700 |
Serial |
448 |
|
Permanent link to this record |
|
|
|
|
Author |
Abakumov, A.M.; Hadermann, J.; Kalyuzhnaya, A.S.; Rozova, M.G.; Mikheev, M.G.; Van Tendeloo, G.; Antipov, E.V. |
|
|
Title |
Ca6.3Mn3Ga4.4Al1.3O18: a novel complex oxide with 3D tetrahedral framework |
Type |
A1 Journal article |
|
Year |
2005 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
|
|
Volume |
178 |
Issue |
10 |
Pages |
3137-3144 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
London |
Editor |
|
|
|
Language |
|
Wos |
000232418200022 |
Publication Date |
2005-08-26 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0022-4596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.299 |
Times cited |
5 |
Open Access |
|
|
|
Notes |
Iap V-1; Rfbr; Intas – Ysf |
Approved |
Most recent IF: 2.299; 2005 IF: 1.725 |
|
|
Call Number |
UA @ lucian @ c:irua:55030 |
Serial |
3520 |
|
Permanent link to this record |
|
|
|
|
Author |
d' Hondt, H.; Hadermann, J.; Abakumov, A.M.; Kalyuzhnaya, A.S.; Rozova, M.G.; Tsirlin, A.A.; Tan, H.; Verbeeck, J.; Antipov, E.V.; Van Tendeloo, G. |
|
|
Title |
Synthesis, crystal structure and magnetic properties of the Sr2Al0.78Mn1.22O5.2 anion-deficient layered perovskite |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
|
|
Volume |
182 |
Issue |
2 |
Pages |
356-363 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
A new layered perovskite Sr2Al0.78Mn1.22O5.2 has been synthesized by solid state reaction in a sealed evacuated silica tube. The crystal structure has been determined using electron diffraction, high-resolution electron microscopy, and high-angle annular dark field imaging and refined from X-ray powder diffraction data (space group P4/mmm, a=3.89023(5) Å, c=7.8034(1) Å, RI=0.023, RP=0.015). The structure is characterized by an alternation of MnO2 and (Al0.78Mn0.22)O1.2 layers. Oxygen atoms and vacancies, as well as the Al and Mn atoms in the (Al0.78Mn0.22)O1.2 layers are disordered. The local atomic arrangement in these layers is suggested to consist of short fragments of brownmillerite-type tetrahedral chains of corner-sharing AlO4 tetrahedra interrupted by MnO6 octahedra, at which the chain fragments rotate over 90°. This results in an averaged tetragonal symmetry. This is confirmed by the valence state of Mn measured by EELS. The relationship between the Sr2Al0.78Mn1.22O5.2 tetragonal perovskite and the parent Sr2Al1.07Mn0.93O5 brownmillerite is discussed. Magnetic susceptibility measurements indicate spin glass behavior of Sr2Al0.78Mn1.22O5.2. The lack of long-range magnetic ordering contrasts with Mn-containing brownmillerites and is likely caused by the frustration of interlayer interactions due to presence of the Mn atoms in the (Al0.78Mn0.22)O1.2 layers. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
London |
Editor |
|
|
|
Language |
|
Wos |
000263124700022 |
Publication Date |
2008-11-14 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0022-4596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.299 |
Times cited |
12 |
Open Access |
|
|
|
Notes |
Iap Vi |
Approved |
Most recent IF: 2.299; 2009 IF: 2.340 |
|
|
Call Number |
UA @ lucian @ c:irua:72943 |
Serial |
3450 |
|
Permanent link to this record |
|
|
|
|
Author |
d' Hondt, H.; Abakumov, A.M.; Hadermann, J.; Kalyuzhnaya, A.S.; Rozova, M.G.; Antipov, E.V.; Van Tendeloo, G. |
|
|
Title |
Tetrahedral chain order in the Sr2Fe2O5 brownmillerite |
Type |
A1 Journal article |
|
Year |
2008 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
|
|
Volume |
20 |
Issue |
22 |
Pages |
7188-7194 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
The crystal structure of the Sr2Fe2O5 brownmillerite has been investigated using electron diffraction and high resolution electron microscopy. The Sr2Fe2O5 structure demonstrates two-dimensional order: the tetrahedral chains with two mirror-related configurations (L and R) are arranged within the tetrahedral layers according to the −L−R−L−R− sequence, and the layers themselves are displaced with respect to each other over 1/2[111] or 1/2[11] vectors of the brownmillerite unit cell, resulting in different ordered stacking variants. A unified superspace model is constructed for ordered stacking sequences in brownmillerites based on the average brownmillerite structure with a = 5.5298(4)Å, b = 15.5875(12)Å, c = 5.6687(4)Å, and (3 + 1)-dimensional superspace group I2/m(0βγ)0s, q = βb* + γc*, 0 ≤ β ≤ 1/2, 0 ≤ γ ≤ 1. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
|
|
Language |
|
Wos |
000261002200039 |
Publication Date |
2008-10-25 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
9.466 |
Times cited |
64 |
Open Access |
|
|
|
Notes |
Iap Vi |
Approved |
Most recent IF: 9.466; 2008 IF: 5.046 |
|
|
Call Number |
UA @ lucian @ c:irua:72945 |
Serial |
3511 |
|
Permanent link to this record |