Table 7. Deviation of DFTB3 Bond Lengths, in Comparison to B3LYP/aug-cc-pVTZ.

bond type	number of comparisons, N	mean absolute deviation, MAD (Å)	mean signed error, MSE (Å)	maximal absolute deviation, MAX (Å)
Cu(I)
Cu–C	13	0.022	+0.019	0.048
Cu–H	1	0.001	–0.001	0.001
Cu–N	15	0.034	–0.018	0.071
Cu–O	8	0.017	+0.001	0.024
Cu–P	8	0.037	+0.037	0.108
Cu–S	18	0.019	+0.007	0.050
Cu(II)
Cu–C	13	0.034	–0.034	0.090
Cu–H	1	0.019	+0.019	0.019
Cu–N	21	0.044	–0.040	0.355
Cu–O	31	0.023	+0.012	0.071
Cu–P	8	0.024	+0.004	0.062
Cu–S	27	0.033	–0.028	0.124