TY - JOUR

T1 - Dynamics of atomic pairs in a Lennard-Jones fluid

T2 - Mean relative displacement analysis

AU - Wu, Ten-Ming

AU - Chang, S. L.

PY - 1999/1/1

Y1 - 1999/1/1

N2 - We have analyzed the dynamics of atomic pairs in a simple fluid in terms of the mean relative displacement of two atoms with a given initial separation. The short-time expansion of the mean relative displacement has been derived exactly beyond the constant acceleration approximation (CAA) (up to the [Formula Presented] order). For a Lennard-Jones fluid, the mean relative displacements calculated by either the CAA or the [Formula Presented]-order approximation have been compared with the results obtained from a molecular-dynamics simulation. Through studying the relative motions of atomic pairs with different initial separations, we give a physical picture of the dynamics of neighboring atoms beyond the CAA.

AB - We have analyzed the dynamics of atomic pairs in a simple fluid in terms of the mean relative displacement of two atoms with a given initial separation. The short-time expansion of the mean relative displacement has been derived exactly beyond the constant acceleration approximation (CAA) (up to the [Formula Presented] order). For a Lennard-Jones fluid, the mean relative displacements calculated by either the CAA or the [Formula Presented]-order approximation have been compared with the results obtained from a molecular-dynamics simulation. Through studying the relative motions of atomic pairs with different initial separations, we give a physical picture of the dynamics of neighboring atoms beyond the CAA.

UR - http://www.scopus.com/inward/record.url?scp=0038650613&partnerID=8YFLogxK

U2 - 10.1103/PhysRevE.59.2993

DO - 10.1103/PhysRevE.59.2993

M3 - Article

AN - SCOPUS:0038650613

VL - 59

SP - 2993

EP - 3000

JO - Physical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics

JF - Physical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics

SN - 1063-651X

IS - 3

ER -