abstract
We argue that the face-centered cubic (fcc) polymeric C-60 phase obtained at 9.5GPa can be mapped onto the classical frustrated Ising fcc antiferromagnet. Extensive density functional theory (DFT) calculations show that at 9.5GPa 56/65 2+2 cycloaddition polymeric bonds are formed between neighboring molecules having different standard orientations but do not form when they have the same standard orientation. These antiferromagnetic bonds cannot be fully satisfied in the fcc lattice of the polymeric phase, resulting in a frustrated structure. By analyzing the ground state configurations of the frustrated Ising fcc antiferromagnet, a picture of the polymeric frustrated structure was obtained.
keywords
HIGH-PRESSURE
subject category
Materials Science; Physics
authors
Laranjeira, J; Marques, L; Mezouar, M; Melle-Franco, M; Strutynski, K
our authors
Jorge Diogo Marques Laranjeira
PhD Student
Karol Strutyński
Assistant Researcher
Leonel Marques Vitorino Joaquim
Assistant Professor
Manuel Melle-Franco
Principal Researcheracknowledgements
Part of this work was developed within the scope of the project CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement (L. Marques, J. Laranjeira, M. Melle-Franco, and K. Strutyski). We warmly thank Jean-Louis Hodeau, Institut Neel, Grenoble, France, for his help during the synchrotron diffraction experiments.