The approximate structure of the 
molecule was predicted
using naïve VESPER theory [11]. This predicts a
tetrahedral arrangement of the ions with a bond angle of
. The average N--H bond length of 1.01 Å was used in
order to construct the initial geometry of the molecule.
A set of calculations with a varying supercell side length (2--7 Å) and cut off energy (100--800 eV) were performed, each with 10 static iterations allowing the electronic state to converge followed by 10 iterations allowing relaxation of the ionic positions. The final atomic positions and energies were found for each. Finally a calculation was performed with a 7 Å cubic supercell and a cut off of 700eV for a total of 30 iterations to ensure the converged structure and total energy of the molecule had been accurately calculated.
The results were analysed to find the average bond angle,
, and bond length, 
, for the molecule and
these were analysed along with the total energy, E, to ascertain their
variation with supercell side length and cut off energy.