Hao, C-M;
Li, Y;
Hong-Mei, H;
Li, Y-L;
(2018)
Structural diversity and electronic properties in potassium silicides.
Journal of Chemical Physics
, 148
(20)
, Article 204706. 10.1063/1.5026699.
Preview |
Text (Author accepted manuscript)
Li_KSi20180508.pdf - Accepted Version Download (1MB) | Preview |
Preview |
Text (Version of record - subject to 12-month embargo)
Li_1.5026699.pdf - Published Version Download (4MB) | Preview |
Abstract
Stable potassium silicides in the complete compositional landscape were systematically explored up to 30 GPa using the variable-composition evolutionary structure prediction method. The results show that K4Si, K3Si, K5Si2, K2Si, K3Si2, KSi, KSi2, KSi3, and K8Si46 have their stability fields in the phase diagram. The spatial dimensional diversity of polymerized silicon atoms (0D “isolated” anion, dimer, Si4 group, 1D zigzag chain, 2D layer, and 3D network) under the potassium sublattice was uncovered as silicon content increases. Especially, the 2D layered silicon presents interestingly a variety of shapes, such as the “4 + 6” ring, “4 + 8”ring, and 8-membered ring. K-Si bonding exhibits a mixed covalency and ionicity, while Si-Si bonding is always of covalent character. Semiconductivity or metallicity mainly depends on the form of sublattices and K:Si ratio, which allows us to find more semiconductors in the Si-rich side when closed-shell K cations are encompassed by polymerized Si. The semiconducting silicides present strong absorption in the infrared and visible light range. These findings open up the avenue for experimental synthesis of alkali metal-IVA compounds and potential applications as battery electrode materials or photoelectric materials.
Type: | Article |
---|---|
Title: | Structural diversity and electronic properties in potassium silicides |
Open access status: | An open access version is available from UCL Discovery |
DOI: | 10.1063/1.5026699 |
Publisher version: | http://dx.doi.org/10.1063/1.5026699 |
Language: | English |
Additional information: | This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions. |
UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Earth Sciences |
URI: | https://discovery.ucl.ac.uk/id/eprint/10048935 |
Archive Staff Only
View Item |