Table 1. Properties of 3-Alkyl-1-[(1R,2S,5R)-(−)-Menthoxymethyl]imidazolium Bis(trifluoromethylsulfonyl)imides, [C_n-im-CH₂OMen][NTf₂] ILs with n = 1–10: Final Mass Fraction Purity, Onset Temperature of Thermal Decomposition T_onset (K), Glass Transition Temperature T_g (K), Density ρ (g·cm^–3) at 298.15 K, and Final Mass Fraction Water Content from Coulometric Carl-Fisher Titration²⁷.

IL [Cn-im-CH2OMen][NTf2]	R	final mass fraction puritya	Tonset (K)b	Tg (K)b	ρ (g·cm–3)c	wH2O·104c
[C1-im-CH2OMen][NTf2]	CH3	0.9996	503.15	229.15	1.3320	1.90
[C2-im-CH2OMen][NTf2]	C2H5	0.9998	498.15	227.15	1.3104	1.13
[C3-im-CH2OMen][NTf2]	C3H7	0.9998	503.15	225.15	1.2875	1.20
[C4-im-CH2OMen][NTf2]	C4H9	0.9998	503.15	222.15	1.2733	1.04
[C5-im-CH2OMen][NTf2]	C5H11	0.9996	503.15	223.15	1.2570	0.76
[C6-im-CH2OMen][NTf2]	C6H13	0.9998	498.15	223.15	1.2350	1.38
[C7-im-CH2OMen][NTf2]	C7H15	0.9998	503.15	222.15	1.2241	0.51
[C8-im-CH2OMen][NTf2]	C8H17	0.9998	498.15	223.15	1.2152	0.97
[C9-im-CH2OMen][NTf2]	C9H19	0.9992	503.15	222.15	1.2008	0.11
[C10-im-CH2OMen][NTf2]	C10H21	0.9999	503.15	222.15	1.1889	0.27

^aValues taken form ref (26) (the same synthetic portion as for viscosity and conductivity measurement).

^bValues taken form ref (25).

^cValues taken from ref (27) (the same synthetic portion after drying as for viscosity and conductivity measurement).