ORIGIN OF THE BA CORE-LEVEL BINDING-ENERGY DIFFERENCE BETWEEN TETRAGONAL AND ORTHORHOMBIC YBA2CU3O7-DELTA

被引:17
作者
PARMIGIANI, F
PACCHIONI, G
BRUNDLE, CR
FOWLER, DE
BAGUS, PS
机构
[1] IBM CORP,ALMADEN RES CTR,DIV RES,SAN JOSE,CA 95120
[2] UNIV MILAN,CTR CNR,DIPARTIMENTO CHIM INORGAN & MET ORGAN,I-20133 MILAN,ITALY
来源
PHYSICAL REVIEW B | 1991年 / 43卷 / 04期
关键词
D O I
10.1103/PhysRevB.43.3695
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
Sintered bulk samples of the orthorhombic, superconducting, phase of YBa2Cu3O7-delta exhibit a congruent-to 1.5 eV Ba core-level decrease compared to the tetragonal, nonsuperconducting phase. This is also observed for thin-film material in the two phases. Using ab initio cluster calculations, we show that shifts of this magnitude are explainable by isotropic contraction of the Ba-O bond length in the 0.01- to 0.02-angstrom range, values compatible with the known lattice-parameter changes between the phases. Finally, even in situ cleaved good-quality single crystals of the orthorhombic phase show a chemically shifted Ba component for some regions of the surface, which may be due to Ba-O bond-length contractions at the surface-vacuum interface.
引用
收藏
页码:3695 / 3698
页数:4
相关论文
共 20 条
[1]  
ALSHAMMA F, 1990, PHYSICA C, V169, P325
[2]   MOLECULAR-ORBITAL THEORY FOR THE ANALYSIS OF PHOTOEMISSION SPECTRA [J].
BAGUS, PS ;
COOLBAUGH, D ;
KOWALCZYK, SP ;
PACCHIONI, G ;
PARMIGIANI, F .
JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA, 1990, 51 :69-74
[3]  
BRUNDLE CR, IN PRESS J ELECT SPE
[4]   GEOMETRICAL BASIS SET FOR MOLECULAR COMPUTATIONS [J].
CLEMENTI, E ;
CORONGIU, G .
CHEMICAL PHYSICS LETTERS, 1982, 90 (05) :359-363
[5]  
DUIJENEVELDT FB, 1972, IBM RJ945 RES REP
[6]   OXYGEN DEFECT IN YBA2CU3OX - AN X-RAY PHOTOEMISSION APPROACH [J].
FORD, WK ;
CHEN, CT ;
ANDERSON, J ;
KWO, J ;
LIOU, SH ;
HONG, M ;
RUBENACKER, GV ;
DRUMHELLER, JE .
PHYSICAL REVIEW B, 1988, 37 (13) :7924-7927
[7]   CORE AND VALENCE XPS SPECTRA OF CLEAN, CLEAVED SINGLE-CRYSTALS OF YBA2CU3O7 [J].
FOWLER, DE ;
BRUNDLE, CR ;
LERCZAK, J ;
HOLTZBERG, F .
JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA, 1990, 52 :323-339
[8]   ARXPS-STUDIES OF C-AXIS TEXTURED SUPERCONDUCTING YBA2CU3OX-FILMS [J].
HALBRITTER, J ;
WALK, P ;
MATHES, HJ ;
HAEUSER, B ;
ROGALLA, H .
ZEITSCHRIFT FUR PHYSIK B-CONDENSED MATTER, 1988, 73 (03) :277-291
[9]   BINDING AND ENERGY-LEVEL SHIFTS OF CARBON-MONOXIDE ADSORBED ON NICKEL - MODEL STUDIES [J].
HERMANN, K ;
BAGUS, PS .
PHYSICAL REVIEW B, 1977, 16 (10) :4195-4208
[10]  
JORGENSEN JD, 1987, PHYS REV B, V36, P3680