title: Nature of Hydrogen Bonds and S···S Interactions in the l-Cystine Crystal.
abstract: The intermolecular interactions that govern the stability of the l-cystine crystal were studied. This task is accomplished by using density-functional theory (DFT) with the generalized-gradient approximation (GGA) and including many-body dispersion (MBD) interactions. The strengths of the different interactions within the molecular crystal were obtained by a decomposition of the total interaction energy in two-, three-, and four-body contributions. It was determined that most of the hydrogen bonds formed within the crystal are strong (13, 15, and 19 kcal/mol) and the van der Waals nature of the S···S interaction is fully confirmed. Also, the presence of strong repulsive three-body contributions is determined. The results obtained support the idea of designing crystal growth inhibitors for this system in such a way that, when inserted in the crystal, they maintain the disulfide bridge environment but its capacity of generate hydrogen-bond networks is removed.
authors.affiliation: Departamento de Química, Área de Fisicoquímica Teórica, Universidad Autónoma Metropolitana-Iztapalapa , Av. San Rafael Atlixco 186, Col. Vicentina CP 09340, México, D.F., Mexico.
authors.forename: Anaid G
authors.initials: AG
authors.lastname: Flores-Huerta
authors.affiliation: Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6, 14195 Berlin, Germany.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Tkatchenko
authors.affiliation: Departamento de Química, Área de Fisicoquímica Teórica, Universidad Autónoma Metropolitana-Iztapalapa , Av. San Rafael Atlixco 186, Col. Vicentina CP 09340, México, D.F., Mexico.
authors.forename: Marcelo
authors.initials: M
authors.lastname: Galván