# Pressure-induced magnetic, structural, and electronic phase transitions in LaFeO{sub 3}: A density functional theory (generalized gradient approximation) + U study

## Abstract

We have investigated the behavior of orthoferrite LaFeO{sub 3} at ambient conditions and under pressure using DFT (generalized gradient approximation (GGA)) + U approach. Ground state electronic (band gap) and magnetic properties are considerably improved due to the Hubbard correction. Moreover, the experimentally observed pressure-driven phase transition, namely, the simultaneous occurrence of spin crossover, isostructural volume collapse, and drastic reduction in electrical resistance (electronic phase transition) is nicely described by GGA + U calculations. In particular, despite a sharp drop in resistance, a small band gap still remains in the low spin state indicating an insulator to semiconductor phase transition, in good agreement with the experiments but in contrast to GGA, which predicts metallic behavior in low spin state. We discuss the origin of variation in electronic structure of LaFeO{sub 3} in low spin state as obtained from GGA to GGA + U methods. These results emphasize the importance of correlation effects in describing the pressure-driven phase transition in LaFeO{sub 3} and other rare-earth orthoferrites.

- Authors:

- EMMG, Physics Division, PINSTECH, P.O. Nilore, Islamabad (Pakistan)
- (Pakistan)

- Publication Date:

- OSTI Identifier:
- 22308724

- Resource Type:
- Journal Article

- Resource Relation:
- Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 2; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; APPROXIMATIONS; COMPUTERIZED SIMULATION; CORRECTIONS; CORRELATIONS; CRYSTAL STRUCTURE; DENSITY FUNCTIONAL METHOD; ELECTRIC CONDUCTIVITY; ELECTRONIC STRUCTURE; FERRITES; GROUND STATES; LANTHANUM COMPOUNDS; MAGNETIC PROPERTIES; PHASE TRANSFORMATIONS; PRESSURE DEPENDENCE; RARE EARTHS; SEMICONDUCTOR MATERIALS; SPIN

### Citation Formats

```
Javaid, Saqib, National Centre of Physics, Islamabad, and Javed Akhtar, M., E-mail: javedakhtar6@gmail.com.
```*Pressure-induced magnetic, structural, and electronic phase transitions in LaFeO{sub 3}: A density functional theory (generalized gradient approximation) + U study*. United States: N. p., 2014.
Web. doi:10.1063/1.4887802.

```
Javaid, Saqib, National Centre of Physics, Islamabad, & Javed Akhtar, M., E-mail: javedakhtar6@gmail.com.
```*Pressure-induced magnetic, structural, and electronic phase transitions in LaFeO{sub 3}: A density functional theory (generalized gradient approximation) + U study*. United States. doi:10.1063/1.4887802.

```
Javaid, Saqib, National Centre of Physics, Islamabad, and Javed Akhtar, M., E-mail: javedakhtar6@gmail.com. Mon .
"Pressure-induced magnetic, structural, and electronic phase transitions in LaFeO{sub 3}: A density functional theory (generalized gradient approximation) + U study". United States.
doi:10.1063/1.4887802.
```

```
@article{osti_22308724,
```

title = {Pressure-induced magnetic, structural, and electronic phase transitions in LaFeO{sub 3}: A density functional theory (generalized gradient approximation) + U study},

author = {Javaid, Saqib and National Centre of Physics, Islamabad and Javed Akhtar, M., E-mail: javedakhtar6@gmail.com},

abstractNote = {We have investigated the behavior of orthoferrite LaFeO{sub 3} at ambient conditions and under pressure using DFT (generalized gradient approximation (GGA)) + U approach. Ground state electronic (band gap) and magnetic properties are considerably improved due to the Hubbard correction. Moreover, the experimentally observed pressure-driven phase transition, namely, the simultaneous occurrence of spin crossover, isostructural volume collapse, and drastic reduction in electrical resistance (electronic phase transition) is nicely described by GGA + U calculations. In particular, despite a sharp drop in resistance, a small band gap still remains in the low spin state indicating an insulator to semiconductor phase transition, in good agreement with the experiments but in contrast to GGA, which predicts metallic behavior in low spin state. We discuss the origin of variation in electronic structure of LaFeO{sub 3} in low spin state as obtained from GGA to GGA + U methods. These results emphasize the importance of correlation effects in describing the pressure-driven phase transition in LaFeO{sub 3} and other rare-earth orthoferrites.},

doi = {10.1063/1.4887802},

journal = {Journal of Applied Physics},

number = 2,

volume = 116,

place = {United States},

year = {Mon Jul 14 00:00:00 EDT 2014},

month = {Mon Jul 14 00:00:00 EDT 2014}

}