Transition metal monocarbonyl molecules

Recent experimental data on the transition-metal diatomics is used to test the "isoelectronic" principle as applied to molecules with the same number of d + s valence electrons. Electron configurations auid ground states in the first-row transition-metal monocarbonyl molecules (MCO) are examined on the basis of their CO stretching frequencies, ESR evidence, auid theoretical calculations. 

Figure 4. Plot of the CO stretching frequencies, v q, in the first-row transition-metal monocarbonyl molecules MCO (circled points are tentative) (49). P gives the variation of the atomic energy of promotion corresponding to 4s 3d ...

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