Note:

It was reported by Dr. B. Yan (Apr/6/2005) that Si_TM.vps gives a relatively larger gap (1.1-1.5 eV) for the bulk Si compared to other LDA gaps (0.4-0.6 eV). This is due to the lack of the non-local part for the d-state. So, it is desirable to use revised pseudo potentials (Si_LDA.vps and Si_GGA.vps), which were generated including the 3d-state, together with revised basis functions Si*.*R.pao.

Non-relativistic pseudo potentials

These pseudo potentials were generated by the TM scheme. PCC below the symbol means that the pseudo potentials were generated under the partial core correction.



• Si_TM.vps

• Si_TM_PCC.vps

Pseudo atomic orbitals for Si_TM.vps and Si_TM_PCC.vps

The number below the symbol means a cutoff radius (a.u.) of the confinement potential. These file includes five radial parts for each angular momentum quantum number l (=0,1,2,3).



• Si5.0.pao

• Si5.5.pao

• Si6.0.pao

• Si6.5.pao

• Si7.0.pao

• Si7.5.pao

Convergence properties with respect to basis sets

Figures (a) and (b) show the convergence properties of the total energy and the equilibrium bond length for a silicon dimer, which are calculated using the basis sets in the database, respectively. The energy cutoff of 113 (Ryd) was used in the numerical integrations and the solution of Poisson's equations. The pseudo potential used in these calculations was Si_TM_PCC.vps which is stored in the vps database. The local spin density approximation (LSDA) was used for the exchange-correlation interaction.

Fully relativistic pseudo potentials

Fully relativistic pseudo potentials generated by the TM scheme within LDA and GGA which contain
• partial core correction
• full relativistic effects including spin-orbit coupling



• Si_LDA.vps

• Si_GGA.vps

Pseudo atomic orbitals for Si_LDA.vps and Si_GGA.vps

The number below the symbol means a cutoff radius (a.u.) of the confinement potential. These file includes five radial parts for each angular momentum quantum number l (=0,1,2,3).



• Si5.0R.pao

• Si5.5R.pao

• Si6.0R.pao

• Si6.5R.pao

• Si7.0R.pao

• Si7.5R.pao

Equilibrium lattice constant and the absolute band gap (calculated with the experimental lattice constant) of the bulk silicon

	Calculated	Other theory	Expt.
lattice constant (Ang)	(a) 5.35, (b) 5.39, (c) 5.41	5.40	5.43
band gap (eV)	(a) 0.54, (b) 0.52, (c) 0.54	0.52	1.17




Refs.

Lattice constant (Exp.)	D. R. Lide, 1993 CRC Handbook of Chemistry and Physics 73rd edn (Boca Raton, FL: Chemical Rubber Company Press)
Lattice constant (Theory)	S. Q. Wang and H. Q. Ye, J. Phys: Condens. Matter 15, L197 (2003)
Band gap (Exp.)	Zahlenwerte und Funktionen aus Naturwissenschaften und Technik, Landolt-Bornstein, New Series (Springer- Verlag, New York, 1982), Vol. III, Pt. 23a.
Band gap (Theory)	W. Ku and A. G. Eguiluz, Phys. Rev. Lett. 89, 126401 (2002)




Calculation conditions
Version	OpenMX2.72
Basis set	(a) Si5.5R-s2p2d1
	(b) Si6.0R-s2p2d1
	(c) Si6.5R-s2p2d1
Pseudo potential	Si_LDA.vps as scalar relativistic VPS
Functional	LDA
spin-orbit coupling	None
Spin non-collinearity	None
Ecut	130 Ryd
k-point	10 x 10 x 10 (for SCF), 15 x 15 x 15 (for DOS)