Table 4. Calculated Diffusion Path Distances, d, and Energy Barriers for Tritium Hops between Different Interstitial Sites in a Li₂TiO₃ Crystal for Different Classes of Independent Local Minimum Energy Paths as Defined by Shi et al.⁹.

		d (Å)		barrier (eV)
diffusion class	pathway	present work	Shi et al.9	present work	Shi et al.9
C1 [Li6–Li6]	1 ↔ 1	1.77	1.68	0.49	0.33
	2 ↔ 2	1.77	1.69	0.51	0.33
	3 ↔ 3	1.98	2.04	0.73	0.55
	1 → 2 (1 ← 2)	1.68	1.58	0.46 (0.45)	0.29 (0.29)
	2 → 3 (2 ← 3)	1.82	1.73	0.60 (0.45)	0.47 (0.30)
	1 → 3 (1 ← 3)	1.86	1.80	0.62 (0.46)	0.48 (0.31)
C2 [Li6–O6]	1 → 4 (1 ← 4)	1.08	1.15	0.09 (0.01)	0.10 (0.00)
	2 → 5 (2 ← 5)	1.08	1.15	0.08 (0.02)	0.09 (0.00)
	3 → 6 (3 ← 6)	1.31	1.41	0.11 (0.16)	0.11 (0.11)
C3 [O6–Li2Ti4–O6]	6 ↔ 6	2.81	2.77	1.07	0.97
	5 ↔ 5	3.11	3.08	1.05	1.00
	4 → 5 (4 ← 5)	3.15	3.12	0.98 (0.98)	0.91 (0.92)
	4 → 6 (4 ← 6)	2.99	2.96	1.00 (0.96)	0.93 (0.86)