Table 1 Fitting results of the Rh K-edge EXAFS spectra by FEFF simulations

Sample	Shell	CN^a	R^b (Å)	σ^2c (Å²)	R factor (%)
Pristine Rh–Co/MOR	Rh–O	6.4^d	2.03	0.0012	0.5
	Rh–Co	3.4^d	2.87	0.0029	0.5
Reduced Rh–Co/MOR	Rh–Co	5.6^e	2.52	0.0041	0.8
Reduced Rh/MOR	Rh–Rh	4.8^e	2.66	0.0049	1.1
Rh foil	Rh–Rh	12^e (12)^f	2.68 (2.68)^f	0.0032	1.0
Rh₂O₃	Rh–O_1st^g	3.0^d (3)^f	2.03 (2.03)^f	0.0019	1.2
	Rh–O_2nd^g	3.0^d (3)^f	2.07 (2.07)^f	0.0019
	Rh–Rh_1st^h	1.0^d (1)^f	2.72 (2.72)^f	0.0018
	Rh–Rh_2nd^h	3.0^d (3)^f	2.99 (2.99)^f	0.0018

^aCoordination number
^bInteratomic distance
^cDebye–Waller factor
^dS₀² = 0.70, determined by curve-fitting analysis of Rh₂O₃ EXAFS to be consistent with the crystallographic data ^eS₀² = 0.88, determined by curve-fitting analysis of Rh foil EXAFS to be consistent with the crystallographic data ^fCrystallography
^gCN, σ², and ΔE were fixed to be the same for Rh–O 1st and 2nd shells and the difference in R was fixed at 0.04 Å, based on crystallographic data ^hσ² and ΔE were fixed to be the same for Rh–Rh 1st and 2nd shells, CN for Rh–Rh_2nd was fixed at three times larger than that for Rh–Rh_1st, and the difference in R was fixed at 0.27 Å, based on crystallographic data

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