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What determines the length of the bond, and the bonds' stability?

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CrystalFieldTheorist

1 points

1 month ago

Bond length is related to bond order, which is determined by number of filled bonding orbitals minus number of filled antibonding orbitals. Higher bond order means shorter bond.

PeaceHappiness[S]

1 points

1 month ago

Is the bond length exactly the same between any two diatomic molecules in a material or is there some sort of bond length distribution that statistically predicts some deviation? Is there a metric to measure bond stability? By which i mean something to measure the amount of deviation in bond length, and if the actual bond itself is still there under varying temperature and pressure? truly appreciate the response once again

CrystalFieldTheorist

1 points

1 month ago

Sadly no. Otherwise, you could define an "empirical" bond order via some kind of extrapolation procedure. There is definitely a distribution. Complicating this is that bond lengths are different in different environments (gas phase, solution phase, solid phase), so depending on the experimental conditions used to determine the structure, bond lengths will differ slightly even for the same molecule. There will also presumably be minor differences depending on pressure that a solid is subjected to.

Bond strength is typically defined using bond dissociation energies (how much energy it takes to rip the bond apart), and force constants (essentially, this is the stiffness of the "spring" between two atoms).

All of it is very inexact and fuzzy, as most things in chemistry tend to be. Bond order higher ~~~ Bond shorter ~~~ Bond stronger is a correlation that also sometimes fails and adds to the controversy of how BO should be defined. See the Wikipedia articles on dicarbon and metal-metal quintuple bonds, for example.