The effect of iodine content in I_x (As₂₀Se₈₀)_100-x where x=0, 4, 8, 12, and 16 atomic % was studied both theoretically and experimentally. The calculated mean coordination number, cohesion energy, mean overall bonding energy, and band gap decrease with iodine content. This is correlated to the decrease of crosslinking by progressive incorporation of iodine. The impact of increasing iodine content on optical properties was studied through the analysis of a single reflection spectrum using Minkov's method. The experimentally evaluated band gap decreases from 1.7 eV to 1.41 eV in good agreement with the different estimations based on Manca's relation. The Urbach energy, related to the structural disorder, increases with the incorporation of iodine. From the measured refraction index, one deduces that the single oscillator energy decreases with iodine content while its dispersion energy increases. The nonlinear optical properties increase substantially with the incorporation of the more polarizable iodine atom.

I _x（As ₂₀ Se ₈₀）_100-x中碘含量的影响其中x = 0、4、8、12和16原子％在理论上和实验上都得到了研究。计算出的平均配位数，内聚能，平均总结合能和带隙随碘含量的增加而降低。这与通过逐步掺入碘而减少交联有关。通过使用Minkov方法分析单个反射光谱，研究了碘含量增加对光学性能的影响。实验评估的带隙从1.7 eV降低到1.41 eV，与基于Manca关系的不同估计非常吻合。与结构紊乱有关的Urbach能量随着碘的掺入而增加。根据测得的折射率，一个推论是，单振荡器能量随碘含量而降低，而其分散能则增加。非线性光学性质随着掺入更多可极化的碘原子而大大增加。