Electronic structure and optical properties of layered ternary transition-metal carbides and nitrides

The electronic structure and optical properties of Ti3AC2 (A=Al, Si, Ge), Ti2AC (A=Al, Ga, In; Si, Ge, Sn; P, As; S), Ti2AlN, M2AlC (M=V, Nb, Cr) and Tan+1AlCn (n=1~4) have been studied using first-principles orthogonalized linear combination of atomic orbitals (OLCAO) method. These layered ternary transition-metal carbides and nitrides are also commonly referred to as "MAX phases". Trends were observed for the calculated density of states (DOS) at Fermi-level, with respect to elemental variations and number of M and X layers. A local minimum of DOS(Ef) was found for Ti3AlC2, Ti2InC and Cr2AlC, predicting relatively high intrinsic structural stability. While a local maximum or an incline was discovered for Ti3GeC2, Ti2GeC, Ti2SnC, Ti2PC, Nb2AlC, Ta2AlC, Ta4AlC3 and Ta5AlC4, indicating their lower intrinsic structural stability. Inter-band optical conductivities showed anisotropy, but not considerable. The reflectance and colors of the MAX phase compounds were also obtained.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Masters

Discipline thesis:degree_discipline

Physics (UMKC)

Grantor dc:publisher

University of Missouri--Kansas City

Year dc:date.issued

2011

Author dc:creator

• Mo, Yuxiang, 1986-

Advisor dc:contributor.advisor

• Ching, Wai-Yim

Language dc:language.iso

en_US

Handle dc:identifier.uri

https://hdl.handle.net/10355/10780

OAI identifier oai:identifier

oai:mospace.umsystem.edu:10355/10780