Theoretical probing of 3d nano metallic clusters as next generation non-linear optical materials

The excess electron containing compounds have exceptional initial hyper polarizabilities (σ), making them promising nominees for next generation non-linear optical materials. We investigated the geometric, thermodynamic, electrical, and nonlinear optical aspects of a highly strained, theoretically designed metallic cluster (MC), (Fe3Se2(CO)8, in this paper. The designed MC was thermally stable. Estimated ionization energy was used to characterize electrical stability nature (IE). Moreover, the significantly reduced EH–L values reflected the MC with its outstanding characteristics. The maximum absorption (λmax) for computed absorption of electronic transitions was estimated between 327 nm and 340 nm and HOMO → LUMO transitions were found to be the dominant electronic transition band in the UV–Vis spectral region. When comparing to the excited spectrum, the stimulated spectrum appeared to be substantially blue-shifted, with a wide band between 400 and 700 nm. It had the hyperpolarizability values of up to 4.3 × 104 au, resulting in a significant drop in excited state and higher hyperpolarizability values. Using the traditional two-level model, the resulting first hyperpolarizability was also explained. In this MC, the projections of hyperpolarizability on dipole moment coincided with overall hyperpolarizability, showing unidirectional charge transfer with polarizability at four basis sets (B3LYP, CAM-B3LYP, WB97XD and PBEPBE). The static second hyperpolarizability (β) value of the examined MC was higher. The recent discovery, we feel, can provide inspiration for further research into alternative excess electron first row transition MC for NLO applications.