Department of Physics, Center for Soft Matter Research, New York University, 4 Washington Place, New York, New York 10003, USA.
Phys Rev Lett. 2014 Nov 21;113(21):215504. doi: 10.1103/PhysRevLett.113.215504.
We study the evolution of structural disorder under cooling in supercooled liquids, focusing on covalent networks. We introduce a model for the energy of networks that incorporates weak noncovalent interactions. We show that at low temperature these interactions considerably affect the network topology near the rigidity transition that occurs as the coordination increases. As a result, this transition becomes mean field and does not present a line of critical points previously argued for, the "rigidity window." Vibrational modes are then not fractons but instead are similar to the anomalous modes observed in packings of particles near jamming. These results suggest an alternative interpretation for the intermediate phase observed in chalcogenides.
我们研究过冷液体中结构无序的冷却演化，重点关注共价网络。我们引入了一个包含弱非共价相互作用的网络能量模型。我们表明，在低温下，这些相互作用会显著影响在配位增加时发生的刚性转变附近的网络拓扑。结果，这个转变变成了平均场，没有以前提出的临界点线，即“刚性窗口”。振动模式不再是分形子，而是类似于在接近堵塞的粒子堆积中观察到的异常模式。这些结果为在硫属化物中观察到的中间相提供了另一种解释。
