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{ X } { Y } { Z } property ::= DYN { R } moment-spec [PAX] { VX } { VY } { VZ } { VR } property ::= DYN TEMPFACTOR

The function of this class of properties is to extract the first
four moments of either the positional or velocity time distribution for
all atoms. The moment-spec specifies which moment or minimum or maximum
of the distribution for each atom to extract. `X`, `Y`, and
`Z` specify the x, y, and z components of the positions. `R`
specifies different things for different moments. For the first moment,
it is the distance between the origin and average coordinates. For the
second through fourth moments, it is the second through fourth power of
the moments summed together and then raised to the reciprocal of the
moment order. For example, `R M4` is

4 4 4 1/4 (M4X + M4Y + M4Z )

`PAX`, which may be specified only for the second through fourth
moments, causes the principal axis values to be used. Note that when
`PAX` is not specified, the cross moment terms are not accessible.
The same rules apply for `VX`, `VY`, `VZ`, and `VR`
except they apply to velocities.

The `TEMPFACTOR` property converts the `DYN R M2`
property into the units used by crystallographers for isotropic
temperature factors.