Defect Structures, Electronic Properties, UV–Vis, and EPR Parameters for Rh 2+ Centers in LiD: A DFT Study

• Published in: physica status solidi (b)
• Main Authors: Wu, Li‐Na, Wu, Shao‐Yi, Liu, Xu‐Sheng, Zhong, Si‐Ying, Zhang, Fu
• Other Authors: National Natural Science Foundation of China
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2018
• Subjects: Orca
• Online Access: http://dx.doi.org/10.1002/pssb.201800026; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fpssb.201800026; https://onlinelibrary.wiley.com/doi/pdf/10.1002/pssb.201800026

The defect structures and electronic properties of orthorhombic elongated (O E ) and tetragonal compressed (T C ) Rh 2+ centers in LiD are theoretically studied using Density Functional Theory (DFT) with the periodic CP2K program. The calculations demonstrate obvious differences in defect structure between the two centers. O E center with one next nearest neighbor (nnn) cation vacancy (V Li ) in [100] axis shows the Jahn‐Teller elongation of about 0.076 Å along [001] axis, whereas T C center with one nnn V Li in [001] axis exhibits a compression of about 0.049 Å along this direction. The ligand between the central Rh 2+ and the V Li is found to move away from the V Li by about 0.038 or 0.035 Å for O­­ E or T C center. The larger magnitude of the overlap population (≈ −0.5907 or −0.5494 e) of the RhD bonds in O E or T C center than that (≈0.2373 e) of the host LiD bonds in pure LiD indicates much stronger covalency of the former. The simulated UV–Vis and electron paramagnetic resonance (EPR) spectra with the embedded cluster model in ORCA code are consistent with the experimental data. The present results are discussed and compared with those of the previous perturbation calculations.