Chirality control of nonplanar lead phthalocyanine (PbPc) and its potential application in high-density storage: a theoretical investigationElectronic supplementary information (ESI) available: Azimuthal orientations of PbPc, the charge density difference and projected density of state at the Pb↑ state, surface reconstruction of top-layer Pd atoms induced by PbPc adsorption, chirality of CuPc on Ag(001) and information storage by controlling the central metal atom up and down. See DOI: 10.1039/c

• Main Authors: Cai, Yingxiang, Xu, Shengliang, Qiao, Xuelei, Wang, Lidong, Liu, Yabo, Wang, Tianyu, Xu, Xuechun
• Format: Article
• Language: English
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/c5cp03355a

On single-crystal surfaces, achiral molecules may become chiral owing to confinement in two dimensions (2D). Metal phthalocyanines (MPcs) on Cu(001) and Ag(100) surfaces have exhibited a chiral electronic state. However, the chirality is not always desirable since crystal defects (grain boundaries) inevitably occur between two different chiral domains during the self-assembly of single layers. In this theoretical study, we propose to utilize metal(001) substrates with different electron configurations to mediate the azimuthal orientations of nonplanar PbPc. The results show that PbPc is chiral on Cu(001) with a partially filled s orbital (3d 10 4s 1 ) but achiral on Pd(001) with a completely filled d orbital (4d 10 ). The mechanism that PbPc prefers achiral azimuthal orientation rather than chiral orientation on Pd(001) is clarified. In addition, we predict that PbPc can form a (3 × 4) surface reconstruction. While it is used for data storage, the capacity is almost three orders of magnitude higher than the present storage materials. Azimuthal orientation of nonplanar PbPc at a stable state mediated by metal(001) substrates.