.... ^2.1

Note: some DL_POLY_2 routines may use the convention that $\mbox{$\underline{r_{ij}}$}=\mbox{$\underline{r}$}_{i}-\mbox{$\underline{r}$}_{j}$.

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...potential!electrostatic. ^2.2

Unlike the other elements of the force field, the electrostatic forces are NOT specified in the input FIELD file, but by setting appropriate directives in the CONTROL file. See section 4.1.1.

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...fieldintro). ^2.3

Strictly speaking, the real space sum ranges over all periodic images of the simulation cell, but in the DL_POLY_2 implementation, the parameters are chosen to restrict the sum to the simulation cell and its nearest neighbours i.e. the minimum images of the cell contents.

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... neutral^2.4

The reader is warned that for the purpose of compatibility with other DL_POLY_2 Ewald routines we have defined $\alpha=0.5/\alpha_{HK}$, where $\alpha_{HK}$ is the $\alpha$ parameter defined by Hautman and Klein in [32].

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... motion.^2.5

An alternative approach is to define ``basic'' and ``secondary'' particles. The basic particles are the minimun number needed to define a local body axis system. The remaining particle positions are expressed in terms of the c.o.m. and the basic particles. Ordinary bond constraints can then be applied to the basic particles provided the forces and torques arising from the secondary particles are transferred to the basic particles in a physically meaningful way.

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... integers^3.1

Important note: For the SPME method the values of kmax1,2,3 should be double those obtained in this prescription, since they specify the sides of a cube, not a radius of convergence.

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