Effects of the CO₂ Guest Molecule on the sI Clathrate Hydrate Structure.

ABSTRACT: This paper analyzes the structural, energetic and mechanical properties of carbon dioxide hydrate clathrates calculated using finite cluster and periodic ab initio density-functional theory methodologies. Intermolecular interactions are described by the exchange-hole dipole moment method. The stability, gas saturation energetics, guest-host interactions, cage deformations, vibrational frequencies, and equation of state parameters for the low-pressure sI cubic phase of the CO₂@H₂O clathrate hydrate are presented. Our results reveal that: (i) the gas saturation process energetically favors complete filling; (ii) carbon dioxide molecules prefer to occupy the larger of the two cages in the sI structure; (iii) blue shifts occur in both the symmetric and antisymmetric stretching frequencies of C

SUBMITTER: Izquierdo-Ruiz F 

PROVIDER: S-EPMC5457105 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature