Enthalpies of formation of the cyanonitrene radical, NCN, were calculated according to the HEAT (High-accuracy Extrapolated Ab initio Thermochemistry) protocol. The obtained, recommended values are 451.7 ±$\pm$ 1.0 kJ mol⁻¹ and 452.2 ±$\pm$ 1.0 kJ mol⁻¹ at 0 K and 298.15 K, respectively (gas phase, 1 bar). The calculated values are in agreement with the most recent Active Thermochemical Tables analysis and some of the previous experimental and computational results. The uncertainties associated with the HEAT values are, however, considerably smaller.

中文翻译：

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NCN自由基的高精度外推从头算热化学

形成cyanonitrene自由基，NCN的焓，根据HEAT（计算ħ IGH-精度ê xtrapolated甲从头b Ť hermochemistry）协议。获得的推荐值为451.7 ±$\pm$1.0 kJ mol ^-1和452.2 ±$\pm$分别在0 K和298.15 K下为1.0 kJ mol ^-1（气相，1 bar）。计算值与最新的“主动热化学表”分析以及一些先前的实验和计算结果一致。但是，与HEAT值相关的不确定性要小得多。