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4 Toward More Sophisticated Problems
LiPF 6 (Solvent) 1
Without LiF
Without LiF
With LiF
With LiF
Solvent:
PC
Solvent:
EC
LiPF 6 (Solvent) 2
LiPF 6 (Solvent) 3
LiPF 6 (Solvent) 4
Fig. 4.26 The optimized structures of LiPF 6 (solvent) n complexes (n = 1–4) after single-electron
reduction. The reduced solvent molecule is shown by the dotted circle. When PF 6
− accepts the
reducing electron, LiF is formed near the system. Reprinted with permission from Xing et al.
(2018). Copyright 2018 American Chemical Society
Number of solvent molecules (n)
Solvation energy (kJ/mol)
Solvation energy (kJ/mol)
EC
PF 6
-
PF 6
-
PC
ΔE = 1.6
(a)
(b)
ΔE = 0.6
Number of solvent molecules (n)
-14
-14
-16
-16
-18
-18
-20
-20
-22
-22
-24
-24
6
2
-
6
2
-
-28
-28
-30
-30
1
1
2
2
4
4
6
6
Fig. 4.27 Plots of {solvation energy of the n th solvent} defined by {LiPF 6 (solvent) n –
LiPF 6 (solvent) n-1 − solvent} (in red) and {solvation energy of PF 6
− with Li + (solvent) n } defined
by {LiPF 6 (solvent) n − Li + (solvent) n − PF 6
− } (in black). For a EC and b PC cases. Reprinted with
permission from Xing et al. (2018). Copyright 2018 American Chemical Society