Thiolate bonds, plastocyanin

More recent calculations have shown qualitatively similar descriptions of plastocyanin, reproducing the Cu-S(thiolate) 7T bonding interaction in the HOMO, however, the sulfur 3p character in the HOMO shows a large dependence on the functional used. Here it should be emphasized that spectroscopic results have provided a very detailed description of the electronic structure of blue copper sites, which have been important for the calibration of electronic-structure calculations. ... 

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