The archetypal NF materials are RM734 and DIO, shown in Figure , both being reported almost simultaneously in 2017 by Mandle et al (RM734) and Nishikawa et al (DIO). In RM734 the orientation of the ester units coupled with the polarity of the terminal nitro group gives a dipole moment of ~11 D (DFT:B3LYP/6-31G(d)). For DIO, the fluorine substitution pattern coupled with ester orientation and also 1,3-dioxanyl ring generate a dipole moment of ~ 9 D (DFT:B3LYP/6-31G(d)). In the NF phase spontaneous polarisations of 6.0 and 3.8 μC cm 2 have been measured for RM734 and DIO, respectively. Figure :