Shiba Hayato, Noguchi Hiroshi
Institute for Solid State Physics, University of Tokyo, Chiba 277-8581, Japan.
Phys Rev E Stat Nonlin Soft Matter Phys. 2011 Sep;84(3 Pt 1):031926. doi: 10.1103/PhysRevE.84.031926. Epub 2011 Sep 27.
Several numerical methods for measuring the bending rigidity and the spontaneous curvature of fluid membranes are studied using two types of meshless membrane models. The bending rigidity is estimated from the thermal undulations of planar and tubular membranes and the axial force of tubular membranes. We found a large dependence of its estimate value from the thermal undulation analysis on the upper-cutoff frequency q(cut) of the least-squares fit. The inverse power-spectrum fit with an extrapolation to q(cut)→0 yields the smallest estimation error among the investigated methods. The spontaneous curvature is estimated from the axial force of tubular membranes and the average curvature of bent membrane strips. The results of these methods show good agreement with each other.
使用两种无网格膜模型研究了几种测量流体膜弯曲刚度和自发曲率的数值方法。弯曲刚度是根据平面和管状膜的热起伏以及管状膜的轴向力来估算的。我们发现，通过热起伏分析得出的其估计值在很大程度上依赖于最小二乘拟合的上截止频率q(cut)。在所研究的方法中，外推到q(cut)→0的逆功率谱拟合产生的估计误差最小。自发曲率是根据管状膜的轴向力和弯曲膜条的平均曲率来估算的。这些方法的结果相互之间显示出良好的一致性。
