Fig. 3. (a) Experimental (Exp., red or blue respectively) and calculated (calcd., black, C4v symmetry @BP86def2/TZVPP-D3BJ, no scaling factor was applied) vibrational spectra of 1 and 2; (b) 14N-NMR-spectra (oDFB, rt, 28.92/21.69 MHz); * signal from N2 atmosphere; (c) crystal structures of 1 (P4/n, R1 = 2.3%, wR2 = 5.7%) and 2 (P4/n, R1 = 2.4%, wR2 = 7.4%) – note that the NO ligand is crystallographically indistinguishable from CO and is only colorized for visual purposes.
