. 2003 Feb;84(2):1370–1386. doi: 10.1016/s0006-3495(03)74952-2

TABLE 2.

Parameters obtained by alternative EXAFS-simulation approaches for the intact Mn complex

			Mn-O (N)			Mn-O (N)			Mn-Mn			Mn-Mn				Mn-Ca (Mn)			Mn-O (N/C)
Sample	Fit no.	n_free	N_I	R_I [Å]	[Å²]	N_II	R_II [Å]	[Å²]	N_III	R_III [Å]	[Å²]	N_IV	R_IV [Å]	[Å²]	N_V	R_V [Å]	[Å²]	N_VI	R_VI [Å]	[Å²]	R_F [%]
PS II in S₁-state	1	8	5.5^*	1.86	0.029				1.30	2.71	0.005							3.4	3.62	0.007	17.8	63
	2	8	5.5^*	1.86	0.029				1.19	2.71	0.005	1.4	3.66	0.014							20.6	85
	3	8	5.5^*	1.86	0.029				1.22	2.71	0.005	1.2	3.19	0.026							25.5	130
	4	9	4.9^†	1.86	0.021	0.6^†	2.16^‡	0.014^‡	1.21	2.71	0.005							3.2	3.62	0.006	9.8	22
	5	9	4.9^†	1.86	0.021	0.6^†	2.16^‡	0.014^‡	1.17	2.71	0.005	1.1	3.67	0.010							12.4	35
	6	9	4.9^†	1.86	0.021	0.6^†	2.16^‡	0.014^‡	0.99	2.71	0.005	1.2	3.19	0.026							19.2	84
	7	10	4.9^†	1.86	0.021	0.6^†	2.16^‡	0.014^‡	1.0^*	2.71	0.004	1.0^*	3.13	0.032				2.9	3.62	0.007	8.0	17
	8	10	4.9^†	1.86	0.021	0.6^†	2.16^‡	0.014^‡	1.0^*	2.71	0.005	0.5^*	3.07	0.004^*	0.5^*	3.29	0.004^*	3.0	3.63	0.008	5.2	7
180 min heated	9	3				6.2	2.16	0.014													16.2	32

In the last row, the fit results obtained for the fully disassembled state (180 min of heating) are shown. EXAFS phase functions were calculated for the absorber-backscatterer combinations shown in the first row; the elements given in parenthesis could also contribute to the respective backscattering shell. Meaning of symbols: N_i, apparent coordination number (per Mn); R_i, mean distance; 2σ_i², Debye-Waller parameter; n_Free, number of independently varied parameters, R_F, filtered R-factor calculated for FT distances ranging from 1.2 to 3.6 Å as a measure for the fit quality (represents deviations in percent). The parameter in the last row represents the so-called goodness of fit, a quadratic error which is corrected for the increase in fit-quality due to an increased number of variable simulation parameters (Teo, 1986; n_max = 16, see text).

Simulation parameters which were fixed (no variation by the curve-fit algorithm).

^†

In fit 4-8, N_I and N_II were variable, but coupled to yield a sum of 5.5.

^‡

RII and 2σ_II² were determined from a fit of the spectrum obtained after 180 min of heating and fixed in the fits of the control spectrum.