Farooqi Bilal Ahmad, Yar Muhammad, Ashraf Ayesha, Farooq Umar, Ayub Khurshid
Institute of Chemistry, University of the Punjab, Lahore, Pakistan.
Department of Chemistry, COMSATS University, Abbottabad Campus, Islamabad, 22060, Pakistan.
J Mol Model. 2020 Nov 4;26(11):332. doi: 10.1007/s00894-020-04590-3.
Density functional theory (DFT) calculations are performed to rationalize the experimentally observed sensitivity and selectivity of polyaniline emeraldine for hydrogen bromide over hydrogen chloride. The interaction behaviour is studied at UB3LYP method of density functional theory through oligomer approach. The properties for polymers are obtained extrapolation through second-degree polynomial fit. Optimized of geometries, interaction energies, Mulliken and natural bond orbital charges are analysed to study the sensing behaviour. In the preferred orientation modes, emeraldine salt acts as a hydrogen donor, whereas HBr and HCl are hydrogen acceptors (nucleophile). Basis set superposition error corrected interaction energies are calculated for accurate determination of interaction strength between sensor and analyte. The basis set superposition error is significant for HBr complex compared to HCl. The decrease in energy gap between highest occupied and lowest unoccupied molecular of conducting polymer (sensor) on complex formation with both analytes has been studied. The results of computational study show that polyaniline emeraldine salt shows more selectivity towards HBr as compared to HCl and this outcome is in agreement with reported results based on experimental observations. Graphical abstract.
进行密度泛函理论（DFT）计算，以合理解释实验观察到的聚苯胺翡翠盐对溴化氢比对氯化氢的灵敏度和选择性。通过低聚物方法，在密度泛函理论的UB3LYP方法下研究相互作用行为。通过二次多项式拟合外推得到聚合物的性质。分析几何结构的优化、相互作用能、穆利肯电荷和自然键轨道电荷，以研究传感行为。在优选的取向模式中，翡翠盐充当氢供体，而HBr和HCl是氢受体（亲核试剂）。计算了基组叠加误差校正的相互作用能，以准确确定传感器与分析物之间的相互作用强度。与HCl相比，HBr配合物的基组叠加误差更为显著。研究了导电聚合物（传感器）与两种分析物形成配合物时，最高占据分子轨道和最低未占据分子轨道之间能隙的减小。计算研究结果表明，聚苯胺翡翠盐对HBr的选择性高于HCl，这一结果与基于实验观察的报道结果一致。图形摘要。
