The paper by Oweimreen commented on hereafter describes density measurements of one of the most thoroughly investigated liquid crystalline compounds, 8CB. The main goal of the paper is to prove that a new "intermediate" phase exists between smectic A (SmA) and nematic (N), referred to as "more ordered nematic" or "less ordered smectic". The first-order character of the transition from smectic A to this intermediate phase is suggested. A detailed discussion of earlier results by other authors for 8CB and other compounds exhibiting the SmA-N phase transition is also presented. The author, however, does not cite or comment on the paper reporting the most precise molar volume measurements of the same phase transition for the same compound, 8CB, published in the same journal in 1999. The present comment provides a missing comparison between the results obtained by Oweimreen using a Paar densimeter and the dilatometric measurements by Zywocinski and Wieczorek.
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