Table 4.

Results of EXAFS data obtained for Np(V) aquo ions, Np(V) humate and Np(V) adsorbed to α-FeOOH and calcite.

System	Np-Oax		Np-Oeq		Reference
	R (Å)	N	R (Å)	N
aquo ion	1.82 ± 0.01	2.5 ± 0.6	2.45 ± 0.02	4.8 ± 1.0	[88]
	1.83	1.6	2.52	5.2	[103]
NpO2(CO3)-	1.82 ± 0.02	2	2.49±0.03	4~5	[104]
Np-humate	1.83	2	2.47	5.3	[105]
Np-geothite	1.85	2.2	2.51	5.5	[103]
Np-calcite	1.85 ± 0.01	2.1 ± 0.2	2.46 ± 0.01	5.1 ± 0.6	[88]