Structural and electronic properties of potassium-doped 1, 2;8, 9-dibenzopentacene superconductor: comparing with doped [7]phenacenes. (16th February 2017)

• Record Type: Journal Article
• Authors: Zhong, Guo-Hua; Zhang, Chao; Yan, Xunwang; Li, Xiaoguang; Du, Zheng; Jing, Gexin; Ma, Cencen
• Is Part Of: Molecular physics. Volume 115:Number 4(2017)
• Page Start: 472
• Page End: 483
• Publication Date: 2017-02-16
• Subjects: Polycyclic aromatic hydrocarbons -- hydrocarbons -- organic superconductor -- dibenzopentacene; Molecules -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Molécules -- Périodiques; Chimie physique et théorique -- Périodiques; 539.6.05
• DOI: 10.1080/00268976.2016.1274439
• Languages: English
• ISSNs: 0026-8976

Abstract

ABSTRACT: Polycyclic aromatic hydrocarbons doped by metal have exhibited the potential of high temperature superconductivity. Understanding the basic properties of materials is the key to reveal the superconductivity. Here, a systemically theoretical study has been done to explore crystal structures and electronic properties of pristine and potassium-doped 1, 2;8, 9-dibenzopentacene, compared with [7]phenacenes case. We determined that vdW-DF2 functional is more suitable to describe the non-local interaction in a molecular crystal. Based on this functional, we predicted the crystal structures and investigated in detail the K atomic positions in a system. It was found that the intralayer doping leads to lower total energy. From the calculated formation energy, for each 1, 2;8, 9-dibenzopentacene molecule, the doping of two electrons is more stable under the relatively K-poor condition while the doping of four electrons is more stable under the K-rich condition. Between these two phases, the three-electron doping phase stabilises in a narrow region of K chemical potential. Combining with the electronic states at Fermi level, we analysed the reasons of superconductivity enhancement in doped 1, 2;8, 9-dibenzopentacene. This work further deepens the understanding of 1, 2;8, 9-dibenzopentacene superconductor. GRAPHICAL ABSTRACT: