The Free Volume Dynamics


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In the present contribution the dynamics of the intermolecular free volume is investigated. For this purpose a new computational algorithm has been proposed and programmed. The free volume is analyzed along the atomistic trajectory obtained by molecular dynamics simulations and a picture on time averaged free volume structure is obtained. The picture showed two distinct regimes of the free volume dynamics at pico-second and nano-second time-scale in liquid. The analysis has shown that at the time scale of the ortho-positronium lifetime and in the liquid phase the free volume microstructure ceases to exist in rigid cavities. This picture is consistent with the common considerations on the o-Ps existence, which suppose the o-Ps atom digging its own holes/cavities in liquids around the temperature of the o-Ps lifetime saturates.



Edited by:

Jozef Krištiak, Jan Kuriplach and Pradeep K. Pujari




D. Račko and J. Krištiak, "The Free Volume Dynamics", Materials Science Forum, Vol. 733, pp. 33-37, 2013

Online since:

November 2012




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