Synthesis, structure, and properties of La[sub 1[minus]x]Sr[sub x]TiO[sub 3] (0 [le] x [le] 1)

Journal Article · · Chemistry of Materials; (United States)

OSTI ID:6722012

Sunstrom, IV, J E; Kauzlarich, S M; Klavins, P ^[1]

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1. Univ. of California, Davis, CA (United States)

The search for a new superconductor in an early transition metal oxide prompted the investigation of the La[sub 1[minus]x]Sr[sub x]TiO[sub 3] series of compounds. The solid solution La[sub 1[minus]x]Sr[sub x]TiO[sub 3] (0 [le] x [le] 1) has been prepared by arc melting stoichiometric amounts of SrTiO[sub 3] and LaTiO[sub 3]. Single-phase samples can be made for the entire stoichiometry range. The polycrystalline samples have been characterized using microprobe, thermogravimetric analysis, powder X-ray and neutron diffraction, temperature-dependent magnetization, and dc resistivity. The compounds crystallize in the orthorhombic space groups Pbnm (x [le] 0.30) and Ibmm (0.30 < x < 0.80), and the cubic space group Pm3m (x [ge] 0.80). The Pbnm structure exists in two forms, O[prime]-orthorhombic (x < 0.10) and O-orthorhombic (0.10 [le] x [le] 0.30), which are a result of Jahn-Teller distortion. The samples x = 0.00, 0.05 are canted antiferromagnets which exhibit a net ferromagnetic moment below 150 K and temperature-independent magnetism from 150 to 300 K. All other compositions show temperature-independent magnetism from 160 to 300 K with some samples (x [ge] 0.50) displaying paramagnetism in the low-temperature range. The temperature dependent resistivity measurements show that the samples are metallic (x [le] 0.70) and semiconducting (x = 0.90). The x = 0.80 sample undergoes a semiconductor-metal transition. The properties of these materials are discussed in reference to the phenomenological phase diagram for perovskites proposed by Goodenough and high-T[sub c] superconductivity.

• OSTI ID: 6722012
• Journal Information: Chemistry of Materials; (United States), Vol. 4:2; ISSN 0897-4756
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
LANTHANUM OXIDES
CRYSTAL STRUCTURE
MAGNETIC PROPERTIES
STRONTIUM OXIDES
TITANIUM OXIDES
CHEMICAL PREPARATION
ELECTRIC CONDUCTIVITY
FERROMAGNETIC MATERIALS
ION MICROPROBE ANALYSIS
MAGNETIZATION
ORTHORHOMBIC LATTICES
SOLID SOLUTIONS
STOICHIOMETRY
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 0065-0273 K
TEMPERATURE RANGE 0273-0400 K
THERMAL GRAVIMETRIC ANALYSIS
ALKALINE EARTH METAL COMPOUNDS
CHALCOGENIDES
CHEMICAL ANALYSIS
CRYSTAL LATTICES
DISPERSIONS
ELECTRICAL PROPERTIES
GRAVIMETRIC ANALYSIS
LANTHANUM COMPOUNDS
MAGNETIC MATERIALS
MATERIALS
MICROANALYSIS
MIXTURES
NONDESTRUCTIVE ANALYSIS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
QUANTITATIVE CHEMICAL ANALYSIS
RARE EARTH COMPOUNDS
SOLUTIONS
STRONTIUM COMPOUNDS
SYNTHESIS
TEMPERATURE RANGE
THERMAL ANALYSIS
TITANIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
360202* - Ceramics
Cermets
&amp; Refractories- Structure &amp; Phase Studies
360204 - Ceramics
Cermets
&amp; Refractories- Physical Properties