Pauling determined an empirical logarithmic dependence of bond order (bond valence), s, to bond length, R, s = exp(R0 – R/ b), where R0 is unit bond length and b is a fitting parameter. Recently, an expression was derived for relating the b fitting parameter to theoretically derived atomic orbital exponents. With a method to calculate b, both R0 and atomic orbital exponents can be experimentally determined through optimized fitting for Cr-O, Cr-S, Mo-O, and Mo-S. In the present study, bond length – valence relationships are found for Cr-O, Cr-S, Mo-O, and Mo-S chemical bonds using published crystallographic data. In addition, atomic orbital exponents were found for chromium and molybdenum: z­­Cr = 1.247 and zMo = 1.381. Finally, bond lengths of unit bond valence, or true single bonds, were found using the bond valence model: Ro(Cr-O) = 1.770 Å, Ro(Cr-S) = 2.159 Å, Ro(Mo-O) = 1.893 Å, and Ro(Mo-S) = 2.264 Å.

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