  In this paper, we introduce Nicil: Non-Ideal magnetohydrodynamics
Coefficients and Ionisation Library. Nicil is a stand-alone Fortran90 module
that calculates the ionisation values and the coefficients of the non-ideal
magnetohydrodynamics terms of Ohmic resistivity, the Hall effect, and ambipolar
diffusion. The module is fully parameterised such that the user can decide
which processes to include and decide upon the values of the free parameters,
making this a versatile and customisable code. The module includes both cosmic
ray and thermal ionisation; the former includes two ion species and three
species of dust grains (positively charged, negatively charged and neutral),
and the latter includes five elements which can be doubly ionised. We
demonstrate tests of the module, and then describe how to implement it into an
existing numerical code.
