  The nitrogen-vacancy (NV) center in diamond is a widely-utilized system due
to its useful quantum properties. Almost all research focuses on the negative
charge state (NV$^-$) and comparatively little is understood about the neutral
charge state (NV$^0$). This is surprising as the charge state often fluctuates
between NV$^0$, and NV$^-$, during measurements. There are potentially under
utilized technical applications that could take advantage of NV$^0$, either by
improving the performance of NV$^-$, or utilizing NV$^0$, directly. However,
the fine-structure of NV$^0$, has not been observed. Here, we rectify this lack
of knowledge by performing magnetic circular dichroism (MCD) measurements that
quantitatively determine the fine-structure of NV$^0$. The observed behavior is
accurately described by spin-Hamiltonians in the ground and excited states with
the ground state yielding a spin-orbit coupling of $\lambda = 2.24 \pm 0.05$
GHz and a orbital $g-$factor of $0.0186 \pm 0.0005$. The reasons why this
fine-structure has not been previously measured are discussed and
strain-broadening is concluded to be the likely reason
