Direct determination of Lennard-Jones crystal surface free energy by a computational cleavage method

Autor(es)

Tipeev, Azat O. ^[1] ; Rino, Jose P. ^[1] ; Zanotto, Edgar D. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Carlos, Dept Phys, Via Washington Luiz, Km 235, BR-13565905 Sao Carlos, SP - Brazil

^[2] Univ Fed Sao Carlos, Dept Mat Engn, Via Washington Luiz, Km 235, BR-13565905 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Chemical Physics; v. 155, n. 9 SEP 7 2021.
• Citações Web of Science: 0

Resumo

The surface free energy of solids, gamma, plays a crucial role in all physical and chemical processes involving material surfaces. For the first time, we obtained gamma directly from molecular dynamics simulations using a crystal cleavage method. The approach was successfully realized in a Lennard-Jones system by inserting two movable external walls, each consisting of a single crystal layer, into a bulk crystal to create flat, defect-free surfaces. The cleavage technique designed allowed us to calculate the surface free energy according to its definition and avoid surface premelting. The temperature dependence of gamma was determined for the (100) and (110) crystal planes along the whole sublimation line and its metastable extension, up to T = 1.02 . T-m, where T-m is the melting point. Good agreement with indirect values of gamma(T) was found. The proposed computational cleavage method can be applied to other solids of interest, providing valuable insight into the understanding of chemical and physical surface processes, and demonstrates the successful import of the cleavage method, traditionally used in technical preparation and study of crystal surfaces, into a modern atomistic simulation. (AU)

• Processo FAPESP: 13/07793-6 - CEPIV - Centro de Ensino, Pesquisa e Inovação em Vidros
• Beneficiário: Edgar Dutra Zanotto
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs
• Processo FAPESP: 17/08350-1 - Cristalização de líquidos super-resfriados através de simulações de dinâmica molecular
• Beneficiário: Azat Tipeev
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado