Two series of semifluorinated-n-alkanes (SFAs) of comparable perfluorinated chain length but, different terminal group constitution, namely perfluoroctyl-n-alkanes [F-(CF2)(8)-(CH2)(n)-H, in, short F8Hn] and perfluoroisononyl-n-alkanes [(CF3)(2)CF(CF2)(6)-(CH2)(n)-H, in short iF9Hn] were synthesized. Their thermal properties were analyzed by means of differential scanning calorimetry (DSC), on both heating and cooling of the samples. The textures of the synthesized semi-fluorinated alkanes were investigated with the microscopy in polarized light. Similar to previously investigated perfluorodecyl-n-alkanes, perfluorooctyl-n-alkanes containing fewer than 12 methylene groups form smectic B phase. F8H8, F8H9, and F8H10 show a tendency to supercool and preserve smectic B ordering even below the transition temperature. For F8H11, the phase transition front smectic B to 3D crystal structure, manifesting itself as a rapid recrystallization., has been. observed. Perfluorooetyl-n-alkanes of 12 or more methylene groups do not form liquid-crystalline phases. In contrast to perfluorooctyl-n-alkanes, perfluoroisononyl-n-alkanes are not capable of liquid-crystalline phase formation, regardless of the hydrogenated moiety length and the experimental conditions.