Iron-based chalcopyrite materials have diverse applications in solar cells, spintronic, thermoelectric devices, LEDs and medical sciences. In this report we have studied structure, electronic and optical properties of chalcopyrite-type nano-cluster XFeY 2 (X=Cu, Ag, Au; Y=S, Se, Te) systematically by using Density Functional Theory (DFT). Our computed HOMO-LUMO energy gap of XFeY 2 is in the range of 1.568–3.982 eV, which endorses its potential application in optoelectronic devices and solar cells. The result shows that chalcopyrite-type material AuFeS 2 having a star-type structure with point group C 2v and sextet spin multiplicity, is the most stable cluster with HOMO-LUMO energy gap of 3.982 eV. The optical properties viz. optical electronegativity, refractive index, dielectric constant, IR and Raman activity of these nano-clusters are also investigated. The result exhibits that HOMO-LUMO energy gap of XFeY 2 along with optical electronegativity and vibrational frequency decreases from S to Se to Te, whereas refractive index and dielectric constant increases in the reverse order.

中文翻译：

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黄铜矿型纳米团簇 XFeY2（X=Cu、Ag、Au；Y=S、Se、Te）的结构、电子和光学性质：密度泛函理论研究

铁基黄铜矿材料在太阳能电池、自旋电子学、热电器件、LED 和医学科学中有多种应用。在本报告中，我们利用密度泛函理论 (DFT) 系统地研究了黄铜矿型纳米团簇 XFeY 2 (X=Cu、Ag、Au；Y=S、Se、Te) 的结构、电子和光学性质。我们计算出的 XFeY 2 的 HOMO-LUMO 能隙在 1.568-3.982 eV 的范围内，这证明了其在光电器件和太阳能电池中的潜在应用。结果表明，黄铜矿型材料AuFeS 2 具有星型结构，具有点群C 2v 和六重线自旋多重性，是最稳定的团簇，HOMO-LUMO能隙为3.982 eV。光学特性即。光学电负性、折射率、介电常数、还研究了这些纳米团簇的红外和拉曼活性。结果表明，XFeY 2 的 HOMO-LUMO 能隙以及光电负性和振动频率从 S 到 Se 再到 Te，而折射率和介电常数以相反的顺序增加。