Exploring the Impact of Hydrogen Interstitial on Structural, Energetic, and Electronic Characteristics within a Carbon Monovacancy

¹ Department of Physics, Tri-Chandra Multiple Campus, Tribhuvan University, Kathmandu, 44600, Nepal
² Department of Physics, RK University, Rajkot- 360020, Gujarat, India
³ Department of EEE, Vardhaman College of Engineering, Hyderabad, Telangana, India

^* Corresponding email id: ashish.tanna@rku.ac.in

Abstract

We discover a unique structural-modified-diamond which exhibits similar symmetry and band gap energy to that of the pure diamond. We study a complex carbon-vacancy-hydrogen in the diamond using the density-functional-theory method. The defective models are created by adding H-interstitial (H_i, where i = 1, 2, 3, and 4) in the 3D diamond C- monovacancy. The result shows that carbon-vacancy-hydrogen defects significantly decreased the symmetry from T_d to C_2V. Likewise, the volumetric size of the systems are widening up to 48.70%, while the optimized band gap energies are narrowing. Additional states appeared in the C-monovacancy, H₁-V, H₂-V, and H₃-V systems which further improved electron mobility. The H_i compensates for the C-monovacancy which further serves as a deep donor. Interestingly, H₄-V exhibits similar symmetry and band gap energy to that of the pure diamond, but its volumetric size is 48.70% wider.