Linear response and stability of ordered phases of block copolymer melts
Linear response and stability of ordered phases of block copolymer melts
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DOI：
10.1021/ma0714316
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发表时间：
2008-02-12
期刊：
影响因子：
5.5
通讯作者：
Morse, David C.
中科院分区：
文献类型：
--
作者：
Ranjan, Amit;Qin, Jian;Morse, David C.
介绍了一种有效的伪谱数值方法，用于计算嵌段共聚物熔体中有序相的线性磁化率的自洽场（SCF）近似（有时称为无规相近似）。我们的方法比施和Laradji及其同事首次计算这个数量时使用的方法更有效，可以研究更强的分离结构。我们重新研究了两嵌段共聚物熔体的几个相的稳定性，发现Laradji等人关于螺旋相稳定性的一些结论是空间分辨率不足的结果。我们发现，一个外延（k = 0）的不稳定性的螺旋相相对于六方相，被认为是以前由Matsen竞争非常密切的不稳定性，发生在一个非零的晶体波矢k。
An efficient pseudo-spectral numerical method is introduced for calculating a self-consistent field (SCF) approximation for the linear susceptibility of ordered phases in block copolymer melts (sometimes referred to as the random phase approximation). Our method is significantly more efficient than that used in the first calculations of this quantity by Shi and Laradji and co-workers, allowing for the study of more strongly segregated structures. We have re-examined the stability of several phases of diblock copolymer melts and find that some conclusions of Laradji et al. regarding the stability of the gyroid phase were the result of insufficient spatial resolution. We find that an epitaxial (k = 0) instability of the gyroid phase with respect to the hexagonal phase that was considered previously by Matsen competes extremely closely with an instability that occurs at a nonzero crystal wavevector k.