naa a22 4500 510734855 CHVBK 20180411083006.0 cr unu---uuuuu 180411e20130901xx s 000 0 eng 10.1007/s12039-013-0470-2 doi (NATIONALLICENCE)springer-10.1007/s12039-013-0470-2 DFT-based inhibitor and promoter selection criteria for pentagonal dodecahedron methane hydrate cage [Elektronische Daten] [SNEHANSHU PAL, T KUNDU] Density functional theory (DFT)-based simulations have been performed to provide electronic structure property correlation based reasoning for conceptualizing the effect of encapsulated methane molecule on the formation of methane hydrate cages, the role of methanol and ethylene glycol as inhibitor and the role of tetra-hydro-furan (THF) and cyclopentane as promoter of methane hydrate. Geometry optimization of 512 cage, 51262 cage and 51264 cage with and without encapsulated methane and the cluster of 512 cage with ethylene glycol, methanol, cyclopentane have been performed by density functional theory using ωB97X-D/6-31+ +G(d,p) method. Methane hydrate formation inhibition by methanol and ethylene glycol as well as methane hydrate stabilization by cyclopentane and tetrahydrofuran are critically analysed based on the interaction energy, free energy change, dipole moment and infrared frequency calculation. Calculation of free energy change for formation of methane hydrate with/without reagents at various temperature and pressure using optimized structure is reported here. It is observed that hydrogen bond between water molecules of clathrate 512 cages become stronger in the presence of cyclopentane and tetrahydrofuran but weaker/broken in the presence of ethylene glycol and methanol. Simulated results correspond well with experimental findings and can be useful for designing new inhibitor and promoter molecules for gas hydrate formation. Graphical Abstract DFT studies have been performed to show the effect of some inhibitor and promoter molecules on pentagonal dodecahedron methane hydrate cage (1CH4@512) structures and electronic properties. It illustrates scientifically the role of promoter (e.g., cyclopentane) and inhibitor (e.g., methanol) on stability and formation possibility of (1CH4@512). Indian Academy of Sciences, 2013 Interaction energy nationallicence red shift nationallicence methane hydrate nationallicence inhibitor nationallicence promoter nationallicence PAL SNEHANSHU Department of Metallurgical and Materials Engineering, Indian Institute of Technology Kharagpur, 721 302, Kharagpur, India aut KUNDU T. Department of Metallurgical and Materials Engineering, Indian Institute of Technology Kharagpur, 721 302, Kharagpur, India aut Journal of Chemical Sciences Springer India 125/5(2013-09-01), 1259-1266 0974-3626 125:5<1259 2013 125 12039 https://doi.org/10.1007/s12039-013-0470-2 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s12039-013-0470-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- PAL SNEHANSHU Department of Metallurgical and Materials Engineering, Indian Institute of Technology Kharagpur, 721 302, Kharagpur, India aut NATIONALLICENCE 700 1- KUNDU T. Department of Metallurgical and Materials Engineering, Indian Institute of Technology Kharagpur, 721 302, Kharagpur, India aut NATIONALLICENCE 773 0- Journal of Chemical Sciences Springer India 125/5(2013-09-01), 1259-1266 0974-3626 125:5<1259 2013 125 12039 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer