Subject spin crossover

The spin crossover phenomenon is known to take place in cubic coordination systems of transition metal compounds (TMC) with electronic configurations that may produce either HS or LS complexes, subject to the strength of the ligand field [24, 25]. For some values of the latter the two electronic configurations, HS... 

Nevertheless, the availability of g and k parameters for Co + permits a reasonable estimate to be made of Bcompiex for CoFe of 787 cm. i (/Ss6 = 0.72). The experimental Dg- value of 1310 cm.-i is subject to some imcertainty by virtue of the dynamic Jahn-Teller effect associated with the upper E state, and is somewhat lower than the value of 1710 cm. i predicted from 10 T>q=f-g, but the experimental and theoretical Dg values lead respectively to Dg/B equal to 1.66 and 2.17, i.e. on either side of the crossover point, and on balance are in accordance with the expectation that Dg/B should lie slightly on the high-spin side of the crossover. It is also noteworthy that the calculated p value agrees extremely closely with that deduced from the tentative assignment of the spin-forbidden transition, (c.f. Section 2 (vi)). 

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