5NC0:
reference: Distinguishing Nitro vs Nitrito Coordination in Cytochrome c' Using Vibrational Spectroscopy and Density Functional Theory., Nilsson ZN, Mandella BL, Sen K, Kekilli D, Hough MA, Moenne-Loccoz P, Strange RW, Andrew CR, Inorg Chem. 2017 Nov 6;56(21):13205-13213. doi: 10.1021/acs.inorgchem.7b01945. PMID: 29053273

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