Structural, Electronic, Dynamic, and Optical Properties of 2D Monolayer Tungsten Telluride (2H-WTe₂) under Small Biaxial Strain Using Density Functional Theory (DFT and DFT + U)

Table 3

The band gap values of monolayer 2H-WTe₂ with respect to GGA and GGA + U.

	GGA	GGA + U	Others	Exp’t.
Band gap (eV) unstrained	1.0439	1.1089	0.974 (GGA) [8] 0.75 (GGA) [26]	—
Band gap (eV) 2% biaxial compression	1.1487	1.2332	—	—
Band gap (eV) 2% biaxial tensile strain	0.9439	0.9945	—	—