  We construct and study a time reversal broken tight binding model on diamond
lattice with complex next-nearest-neighbour hopping which can be thought of as
a generalisation of two dimensional Haldane model in three dimension. The model
also breaks inversion symmetry owing to sub-lattice dependent chemical
potential. We calculate the spectrum of the model and find the existence of six
pairs of anisotropic gapless points with linear dependence on momentum. The
coordinates of the gapless points are ($2 \pi, \pi \pm k_0,0),~ (2 \pi, \pi \pm
k_0,2 \pi)$ and their possible permutations . The condition for gapless
spectrum is very similar to the two dimensional case. Each gapless points are
having well defined chirality and in the gapless phase specific set of planes
have non-zero Chern number. The gapped phase is a trivial bulk insulator which
has vanishing Chern number as well as Hopf index. The model belongs to the
symmetry class AIII according to the ten-fold way of classification.
Surprisingly the gapless phase does contain a gapped surface state where as the
gapped state has a gapless surface states as found in (1,1,1) direction.
