Hussain Fakhar, Hussain Riaz, Irshad Zobia, Hussain Muzammil, Khan Muhammad Usman, Yaqoob Junaid, Ayub Khurshid, Adnan Muhammad
Department of Chemistry, University of Okara, Okara 56300, Pakistan.
Graduate School of Energy Science and Technology, Chungnam National University, Daejeon 34134, Republic of Korea.
J Phys Chem A. 2025 Aug 28;129(34):7853-7862. doi: 10.1021/acs.jpca.5c04139. Epub 2025 Aug 13.
Nonlinear optical (NLO) materials play a pivotal role in controlling laser characteristics, including phase and frequency, making them essential for optoelectronic applications. This study presents a quantum chemical investigation into the effects of copper doping on the NLO properties of small gold clusters. Using density functional theory with the CAM-B3LYP/LanL2DZ level of theory, we examined both pure (Au, where 8 ≤ ≤ 10) and copper-doped (AuCu) gold clusters. To the best of our knowledge, no theoretical studies have been reported on the nonlinear optical properties of pure and Cu-doped clusters. Copper incorporation leads to a marked reduction in the HOMO-LUMO energy gap from 4.77 eV down to 1.59 indicating enhanced NLO response. The dynamic NLO properties were computed at a standard Nd:YAG laser wavelength (1064 nm; ω = 0.0428 au). Among the doped clusters, AuCu exhibited the highest first hyperpolarizability β, reaching 5.27 × 10 au. The second hyperpolarizability γ peaked at 3.89 × 10 au for AuCu, while the third-order response γ was highest for AuCu at 1.03 × 10 au. These results highlight copper-doped gold clusters as promising candidates for the development of high-performance NLO materials, with potential applications in next-generation electronic and photonic devices.
非线性光学（NLO）材料在控制激光特性（包括相位和频率）方面起着关键作用，使其成为光电应用中必不可少的材料。本研究对铜掺杂对小金团簇非线性光学性质的影响进行了量子化学研究。使用密度泛函理论，采用CAM - B3LYP/LanL2DZ理论水平，我们研究了纯金团簇（Au，其中8≤≤10）和铜掺杂的金团簇（AuCu）。据我们所知，尚未有关于纯金团簇和铜掺杂团簇非线性光学性质的理论研究报道。铜的掺入导致HOMO - LUMO能隙从4.77 eV显著降低至1.59 eV，表明非线性光学响应增强。在标准的Nd:YAG激光波长（1064 nm；ω = 0.0428 au）下计算了动态非线性光学性质。在掺杂团簇中，AuCu表现出最高的第一超极化率β，达到5.27×10 au。对于AuCu，第二超极化率γ峰值为3.89×10 au，而三阶响应γ对于AuCu最高，为1.03×10 au。这些结果突出了铜掺杂金团簇作为开发高性能非线性光学材料的有前途的候选者，在下一代电子和光子器件中具有潜在应用。
