TY - JOUR

T1 - Transformation of hydrogen bond network during CO2 clathrate hydrate dissociation

AU - Gets, Kirill

AU - Belosludov, Vladimir

AU - Zhdanov, Ravil

AU - Bozhko, Yulia

AU - Belosludov, Rodion

AU - Subbotin, Oleg

AU - Marasanov, Nikita

AU - Kawazoe, Yoshiyuki

N1 - Publisher Copyright: © 2019 Elsevier B.V.

PY - 2020/1/1

Y1 - 2020/1/1

N2 - The kinetic process of the solid-liquid first-order phase transition of carbon dioxide CS-I hydrates with various cavity occupation ratios has been investigated in order to understand the framework of the H-bond network and the local structure of each water molecule. This includes the time dependent change in short-range order at temperatures close to the melting point and comparison with the hexagonal ice structure. Using the molecular dynamics method, dependencies of the internal energy of the studied systems on the time of heating were found. Jumps in the internal energy of solids in the range at 275–300 K indicate a phase transition. The study of the oxygen‑oxygen radial distribution and hydrogen‑oxygen‑oxygen mutual orientation angles between molecules detached at no >3.2 Å led to the determination of the H-bond coordination number for all molecules and the total number of H-bonds and showed instantaneous (<1 ns) reorganization of the short-range order of all molecules. Structural analysis of neighbor water molecule pairs showed ~10–15% decrease in the H-bond number after melting whereas all molecules form a single long-range H-bond network. Analysis of the H-bond network showed minor changes in the H-bond interaction energy at the solid-liquid phase transition.

AB - The kinetic process of the solid-liquid first-order phase transition of carbon dioxide CS-I hydrates with various cavity occupation ratios has been investigated in order to understand the framework of the H-bond network and the local structure of each water molecule. This includes the time dependent change in short-range order at temperatures close to the melting point and comparison with the hexagonal ice structure. Using the molecular dynamics method, dependencies of the internal energy of the studied systems on the time of heating were found. Jumps in the internal energy of solids in the range at 275–300 K indicate a phase transition. The study of the oxygen‑oxygen radial distribution and hydrogen‑oxygen‑oxygen mutual orientation angles between molecules detached at no >3.2 Å led to the determination of the H-bond coordination number for all molecules and the total number of H-bonds and showed instantaneous (<1 ns) reorganization of the short-range order of all molecules. Structural analysis of neighbor water molecule pairs showed ~10–15% decrease in the H-bond number after melting whereas all molecules form a single long-range H-bond network. Analysis of the H-bond network showed minor changes in the H-bond interaction energy at the solid-liquid phase transition.

KW - CO gas hydrate

KW - Hydrogen bond network

KW - Molecular dynamics simulation

KW - Phase transitions

KW - Short-range order

KW - MOLECULAR-DYNAMICS

KW - CO2 gas hydrate

KW - DIRECT COEXISTENCE

KW - SIMULATION

KW - SEQUESTRATION

KW - WATER MODELS

KW - METHANE HYDRATE

KW - GAS

KW - MELTING-POINT

KW - FREE-ENERGY

KW - PHASE-DIAGRAM

UR - http://www.scopus.com/inward/record.url?scp=85074720687&partnerID=8YFLogxK

U2 - 10.1016/j.apsusc.2019.143644

DO - 10.1016/j.apsusc.2019.143644

M3 - Article

AN - SCOPUS:85074720687

VL - 499

JO - Applied Surface Science

JF - Applied Surface Science

SN - 0169-4332

M1 - 143644

ER -