CrN, CuB, and AuB: A tale of two dissociation limits
DM Merriles, MD Morse - The Journal of Physical Chemistry …, 2023 - ACS Publications
The Journal of Physical Chemistry Letters, 2023•ACS Publications
Predissociation thresholds corresponding to dissociation at ground state separated atom
limits (SALs) have been recorded in this group for more than 100 d-and f-block metal-
containing molecules. The metal atom electronic degeneracies in these molecules generate
a dense manifold of electronic states that allow high-lying vibronic levels to couple to
pathways leading to dissociation. However, CrN, CuB, and AuB fail to dissociate at their
ground SAL. Instead, the molecules remain bound at energies that far surpass their bond …
limits (SALs) have been recorded in this group for more than 100 d-and f-block metal-
containing molecules. The metal atom electronic degeneracies in these molecules generate
a dense manifold of electronic states that allow high-lying vibronic levels to couple to
pathways leading to dissociation. However, CrN, CuB, and AuB fail to dissociate at their
ground SAL. Instead, the molecules remain bound at energies that far surpass their bond …
Predissociation thresholds corresponding to dissociation at ground state separated atom limits (SALs) have been recorded in this group for more than 100 d- and f-block metal-containing molecules. The metal atom electronic degeneracies in these molecules generate a dense manifold of electronic states that allow high-lying vibronic levels to couple to pathways leading to dissociation. However, CrN, CuB, and AuB fail to dissociate at their ground SAL. Instead, the molecules remain bound at energies that far surpass their bond dissociation energies (BDEs), and their bonds break only when excited at or above an excited SAL. Sharp predissociation thresholds at excited SALs nevertheless allowed BDEs to be derived: D0(CrN): 3.941(22) eV; D0(CuB): 2.26(15) eV; D0(Au11B): 3.724(3) eV. A previous measurement of D0(AlCr) is re-evaluated as dissociating to a higher energy limit, giving a revised value of D0(AlCr) = 1.32(2) eV. A discussion of this physical behavior is presented.
ACS Publications