3184.     SIDGWICK, N. V., AND BAILEY, R. W.  Structures of the Metallic Carbonyl and Nitrosyl Compounds.  Proc. Roy. Soc. (London), vol. 144, A, 1934, pp. 521-537; Chem. Abs., vol. 28, 1934, p. 4676.

                    For the compounds Mx(CO)y (NO)z, G-[(xm+2y+3z)/x]=x-1: (m=atomic number of M. G.=atomic number of the next inert gas).  For carbonyls (z=0) the binding must be M^--C^--M^-; if x=1, the link is linear; x=3, triangular, x=4, tetrahedral; a CO is on each edge.  The crystal structures of Fe₂ (CO)₉ and Fe₃(CO)₁₂ are compatible with this.  For ntrosyis, the binding is M^---N^-=O^-.  Nearly all the carbonyls and a great many nitrosyls obey these rules.

        SIDOROV, N. V.  See abs. 2757, 3364, 3365, 3366.