Mass tensor molecular dynamics

If one replaces the ordinary kinetic energy function for a classical system of point masses (( 1 2 Σi=1N mi q ̇i2) by a more general quadratic form ( 1 2 Σij=1N q ̇iMij q ̇j), where Mij is an arbitrary positive-definite symmetric "mass tensor," one obtains a system having different dynamics but the same equilibrium properties as the original system. By appropriate choice of Mij, high frequency motions can be slowed down and low frequency ones speeded up, thereby increasing the efficiency with which configuration space can be explored in a given amont of computer time. Tests of the method on a short Lennard-Jones polymer chain indicate that a five- to tenfold saving of computer time is possible for such systems. © 1975.