The Laser Ablation Production of Platinum Nitride and its Possible Structure

The synthesis of platinum nitride by the laser ablation method is reported. The spectroscopic results show that nitrogen is in interstitial sites of platinum as N-units, contradicting the accepted configuration for PtN2 where it is as N2-units. To elucidate this point we did density functional calculations to correlate composition with nitrogen sites. For dilute nitrogen concentrations, x < 0.2, nitrogen would be in six-fold coordinated sites (octahedral interstices) as N-units. For 0.2 < x < 1.5, nitrogen would be in tetrahedral interstices as N-units. Only for x > 1.5 the N2-configuration in octahedral sites is attained.