Electronic-Structures Calculations of Calcium-Intercalated Bilayer Graphene: A First-Principle Study

Sri Hidayati (Computational Physics Research Group, Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara BLS 21, Yogyakarta 55281, Indonesia Department of Physics, Faculty of Science and Technology, Universitas )
Iman Santoso (Computational Physics Research Group, Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara BLS 21, Yogyakarta 55281, Indonesia)
Sefty Yunitasari (Computational Physics Research Group, Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara BLS 21, Yogyakarta 55281, Indonesia)
Sholihun Sholihun (Computational Physics Research Group, Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara BLS 21, Yogyakarta 55281, Indonesia)

Indonesian Journal of Chemistry
Vol 22, No 6 (2022)

In this study, electronic structure calculations of Ca-intercalated bilayer graphene are conducted using the density functional theory (DFT). We modeled two configurations by positioning calcium in the middle of the bilayer (M-site) and on top of the bilayer surface (T-site). Our results show that the Dirac point is shifted below the fermi level. The approximated critical temperature is 7.9 K. We then calculated the electron transfer and formation energy for each system. We found that, for the M-site, the electron transfer increased as the Ca concentration increased, while the reverse occurred for T-site. The calculated formation energies were negative, meaning that all configurations were spontaneously created. In other words, the involved reactions were exothermic.