We performed first-principle calculations based on density functional theory to investigate structural, electronic, optical, vibrational, and thermodynamic properties of the dopamine hydrochloride and Levodopa hydrochloride crystals. Our results showed a good agreement between the optimized structures and those determined previously by X-ray diffraction. The theoretical band gap of dopamine hydrochloride crystal was found to be indirect, whereas Levodopa hydrochloride showed a direct band gap. The calculated optical absorption of both crystalline structures occurs in the UV region, showing greater sensitivity to electromagnetic radiation with an energy of approximately 6 eV, and dielectric constant equal to 2.13 (2.15) for dopamine (Levodopa).

我们基于密度泛函理论进行了第一性原理计算，以研究多巴胺盐酸盐和左旋多巴盐酸盐晶体的结构，电子，光学，振动和热力学性质。我们的结果表明，优化结构与先前通过X射线衍射确定的结构之间具有良好的一致性。发现多巴胺盐酸盐晶体的理论带隙是间接的，而盐酸左旋多巴显示出直接带隙。计算出的两个晶体结构的光吸收发生在紫外线区域，显示出对电磁辐射的更高敏感性，能量约为6 eV，多巴胺（左旋多巴）的介电常数等于2.13（2.15）。