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Updated: May 30, 2026
11:07
Synthesis of Non-uniformly Pr-doped SrTiO3 Ceramics and Their Thermoelectric Properties
Published on: August 15, 2015
Crossover from itinerant-electron to localized-electron behavior in Sr(1-x)Ca(x)CrO3 perovskite solid solution
Youwen Long1, Liuxiang Yang, Yuxi Lv
1Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China. ywlong@iphy.ac.cn
Summary
This study explores Sr(1-x)Ca(x)CrO(3) perovskites, revealing structural phase transitions and magnetic ordering. Calcium substitution influences electrical properties, shifting from semiconducting to variable-range hopping behavior.
Area of Science:
- Materials Science
- Solid-State Physics
- Crystallography
Background:
- Perovskite oxides exhibit diverse electrical and magnetic properties.
- Tuning chemical composition can alter material characteristics.
Purpose of the Study:
- Investigate structural, magnetic, and electrical properties of Sr(1-x)Ca(x)CrO(3) solid solutions.
- Determine the impact of calcium substitution on perovskite phase transitions and electronic behavior.
Main Methods:
- High-pressure and high-temperature synthesis of polycrystalline Sr(1-x)Ca(x)CrO(3) samples.
- Rietveld analysis for structural characterization.
- Magnetic ordering temperature (T(N)) and electrical transport measurements.
Main Results:
- Structural phase transitions observed from cubic to tetragonal to orthorhombic with increasing calcium content (x).
- Antiferromagnetic ordering occurs in non-cubic phases, with T(N) increasing with x.
- Electrical properties transition from semiconducting to variable-range hopping with increasing x.
- An insulator-metal transition is observed under pressure, influenced by calcium content.
Conclusions:
- Calcium substitution induces structural and magnetic changes in SrCrO(3) perovskites.
- The π(∗)-band model explains the observed electronic behavior, linking it to calcium ion size and acidity.
- Ca(2+) substitution narrows the π(∗)-band, promoting a transition from itinerant to localized electron behavior.
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