# Is it a “Bary center” or a “Bari center”?

(Studying Coordination Chemistry, "Crystal Field Theory" at school)

Apparently, different sources spell this differently.

The Wikipedia article on Crystal Field Stabilization Energy, calls it the "Barycenter" (as does my school textbook)

However, the actual Wikipedia article on the "Barycenter" refers to, (as far as I can tell) the center of mass of two mutually orbiting bodies. Whereas the "Bary/Baricenter" I'm talking about is the zero-energy reference level in octahedral complexes.

Another book I have at hand (Concise Inorganic Chemistry Lee, J.D), prominently uses the term "Bari centre".

The center/centre distinction aside, what I've been able to glean from my books (and the internet), is that this term is spelled in four different ways (Wah! Such gross inconsistency in literature!):

• Barycenter
• Bary center
• Baricenter
• Bari center

But which one's correct (or at least, a more preferred term in Chemistry-literature)?

• "barycentre" is the original spelling of the word. books.google.com/… so none of the above – DavePhD Dec 8 '17 at 18:50
• My Greek roots say barycenter, though I'll allow DavePhD's variant. – Zhe Dec 8 '17 at 18:53
• But here it is written "bari"center :(. – Nilay Ghosh Dec 9 '17 at 3:23
• – Karl Dec 9 '17 at 9:54
• @Karl Yep, it seems now that "barycenter/re" is the more widely used term; the question now, would be whether it applies to the Crystal Field Theory as well as two-body systems (the links suggest the latter). Thanks for the link! O:) – paracetamol Dec 9 '17 at 10:07

In Crystal Field Theory (CFT), electrons in the $$\mathrm{d}$$-orbitals are repelled to different degrees by the ligands. The degeneracy of the $$\mathrm{d}$$-orbitals is lifted. The Barycenter is the average energy of the $$\mathrm{d}$$-orbitals (Coordination Chemistry II: Theories of Electronic Structure and Crystal Field Theory):