A New Crystal Phase of Terephthal - bis - n - butylaniline

Abstract

Terephthal-bis-n-butylaniline (TBBA) is known to present nine phases : one isotropic, one nematic, five smectic, and two crystalline solid phases as shown in Figure 1.¹ A large number of investigations have been made in order to clarify the nature of each smectic phase from various points of view. Recently, Doucet et al. have determined the detailed crystal structure of phase VIII (monoclinic system, space group C2/c, and unit cell dimensions a=53.2 A, b=5.75 A, c=17.57 A, and β=115.47°) and also the lattice constants of the low-temperature phase IX at -50°C (triclinic system, a=26.8 A, b=5.75 A, c=17.52 A, α=83.5°, β=121.2°, and γ=96.5°).²