اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدالرسم البياني للنيماتيك النووي الجوزي
Phase diagram of Gaussian-core nematics
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نحن ندرس نموذج بسيط لنظام كريستال مذاب نيماتيك مصنوع من جسيمات مستطيلة متوازية تتفاعل عبر قانون جاذب كاذب. بعد التعرف على الأشكال الصلبة الملائمة للنظام من خلال فحص دقيق لأربعة عشرة هيكل كريستال في درجة حرارة صفر، نحدد درجة حرارة الذهاب للذبذب لقيم مختلفة من الضغط، كذلك من خلال حسابات الطاقة الحرة الدقيقة. ومن بين الميزات الرئيسية لهذا النموذج هي الذبذب المعادي الذي يسببه الضغط وتثبيط الطور العمودي لدرجات حرارة متوسطة.
We study a simple model of a nematic liquid crystal made of parallel ellipsoidal particles interacting via a repulsive Gaussian law. After identifying the relevant solid phases of the system through a careful zero-temperature scrutiny of as many as eleven candidate crystal structures, we determine the melting temperature for various pressure values, also with the help of exact free energy calculations. Among the prominent features of this model are pressure-driven reentrant melting and the stabilization of a columnar phase for intermediate temperatures.
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