HONPAS (Hefei Order-N Packages for Ab initio Simulations) is an ab initio electronic structure calculation software package for linear scaling first-principles density functional theory (DFT) calculations of large-scale systems with standard norm-conserving pseudopotentials and numerical atomic orbitals (NAOs) under the periodic boundary conditions. HONPAS is developed in the framework of the SIESTA methodology and focuses on the development and implementation of efficient linear scaling algorithms for ab initio electronic structure calculations.

HONPAS（Hefei Order-N Packages for Ab initio Simulations）是一个从头计算电子结构计算软件包，用于在周期性边界条件下对具有标准范数守恒赝势和数值原子轨道（NAOs）的大系统进行线性标度第一性原理密度泛函理论（DFT）计算。HONPAS是在SIESTA方法的框架内开发的，专注于开发和实施用于从头计算电子结构计算的高效线性缩放算法。