Series of non-symmetric liquid crystal dimers, -(4-benzylidenechloroaniline-4'-oxy)--[4-(thiophene-2-carboxyl)benzylideneaniline-4'-oxy]alkanes incorporating a thiophene-based moiety in one of the two mesogenic units have been synthesized and characterized. The nematogenic properties of the dimers were studied wherein the flexible spacers made up by n methylene units (-CH2-) ranging from n=5 to n=12. These dimers exhibit enantiotropic N phase with high thermal stability (187.0 degrees C). The N phase temperature range for the present homologues is found to be strongly dependent on the length and parity of the methylene spacer which connects the 4-benzylidenechloroaniline and 4-(thiophene-2-carboxyl)- benzylideneaniline mesogenic cores.