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For the astronomical distance measure, see parsec.
One of the strengths of this code is that it handles non-periodic boundary conditions in a natural way, without the use of super-cells, but can equally well handle periodic and partially periodic boundary conditions. Another key strength is that it is readily amenable to efficient massive parallelization, making it highly effective for very large systems.
Kronik, Leeor; Makmal, Adi; Tiago, Murilo L.; Alemany, M. M. G.; Jain, Manish; Huang, Xiangyang; Saad, Yousef; Chelikowsky, James R. (2006). "PARSEC – the pseudopotential algorithm for real-space electronic structure calculations: recent advances and novel applications to nano-structures". Physica Status Solidi B. 243 (5): 1063–1079. Bibcode:2006PSSBR.243.1063K. doi:10.1002/pssb.200541463. ISSN0370-1972. S2CID122821136.
Natan, Amir; Benjamini, Ayelet; Naveh, Doron; Kronik, Leeor; Tiago, Murilo L.; Beckman, Scott P.; Chelikowsky, James R. (2008-08-12). "Real-space pseudopotential method for first principles calculations of general periodic and partially periodic systems". Physical Review B. 78 (7): 075109. Bibcode:2008PhRvB..78g5109N. doi:10.1103/physrevb.78.075109. ISSN1098-0121. S2CID123147721.