The effects of the non-ideality (NI) of the classical plasmas on the doubly excited singlet S states in the positronium negative ion (Ps\(^-\)) are investigated. The organised effect of the plasma is taken care of by means of a pseudopotential which is characterised by the Debye length D and the non-ideality parameter \(\gamma \). Using an extensive wavefunction within the framework of the stabilization method, it has been possible to identify four doubly excited states (DES) in Ps\(^-\). The convergence of the energy and the width of those states are corroborated by increasing the number of terms in the wavefunction. Our present calculation for the plasma-free case reproduces the established results. An inclusive study is made to quantify and qualify the changes experienced by the energies and the widths of those states due to the influence of the NI over a wide range. It is observed that the energy of each DES increases and the width of each DES diminishes due to the effect of the increasing NI of the plasma.

研究了经典等离子体的非理想性（NI）对正电子负离子（Ps \(^-\) ）中双激发单线态 S 态的影响。等离子体的组织效应是通过赝势来处理的，赝势的特征是德拜长度D和非理想参数\(\gamma \)。在稳定方法的框架内使用广泛的波函数，可以识别 Ps \(^-\)中的四个双激发态 (DES) 。通过增加波函数中的项数来证实能量的收敛和这些状态的宽度。我们目前对无血浆情况的计算再现了既定结果。进行了一项包容性研究，以量化和限定由于 NI 在大范围内的影响而导致这些状态的能量和宽度所经历的变化。可以观察到，由于等离子体 NI 增加的影响，每个 DES 的能量增加，每个 DES 的宽度减小。