In the paper we propose and test a "gel-drying" method of obtaining porous oxide glasses in Molecular Dynamics (MD) simulations. The simulation is started with low (screened) values of ionic charges. Then, the charges are gradually increased (to mimic the gradually elimination of a polar solvent) up to full ionic charges (a completely dry gel). This computational trick is applied to produce a porous PbSiO3 system. The structure of the resulting low-density samples is analysed in detail. Then, the porous structures are submitted to spontaneous densification, and the structure of the obtained dense bulk glasses id analysed. Finally,the structures of bulk glass obtained via spontaneous densification (density p=8250kg/m3) and bulk glass of the same density obtained via isotropic compression are compared.
The structure of porous and spontaneously densified amorphous PbSiO3: a molecular dynamics study
FELIZIANI, Sandro;FRIGIO, Sandro;
2004-01-01
Abstract
In the paper we propose and test a "gel-drying" method of obtaining porous oxide glasses in Molecular Dynamics (MD) simulations. The simulation is started with low (screened) values of ionic charges. Then, the charges are gradually increased (to mimic the gradually elimination of a polar solvent) up to full ionic charges (a completely dry gel). This computational trick is applied to produce a porous PbSiO3 system. The structure of the resulting low-density samples is analysed in detail. Then, the porous structures are submitted to spontaneous densification, and the structure of the obtained dense bulk glasses id analysed. Finally,the structures of bulk glass obtained via spontaneous densification (density p=8250kg/m3) and bulk glass of the same density obtained via isotropic compression are compared.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.