Density functional investigation on the Structural, electronic and optical properties of cadmium chalcogenides clusters CdnXm (n = 1–3, m = 1–3; X = O, S, Se, Te)

[Display omitted] •Reports structural, electronic and optical properties of 36 CdnXm (n, m = 1–3; X = O, S, Se, Te) clusters.•DFT based energy gain (ΔE) computation develop a novel extraordinarily stable Cd3O3 cluster.•Cd3O3 signifies stability as well visible active (λ = 472.4 nm) cluster with future promises.•Simulated IR spectra may certainly guide experimentalist for possible synthesis of its or its assembled materials. A comprehensive investigation on the various properties such as structural, electronic and optical properties of the series of cadmium chalcogenide clusters, viz. CdnXm (n, m = 1–3, X = O, S, Se, Te) using the density functional theory (DFT) is reported in this paper. The electronic properties of all the clusters, including the HOMO-LUMO gap (HLG), ionization potential (IP), electron affinity (EA), chemical hardness (η), and electrophilicity index (ω) has been carried out under conceptual DFT formalism. To explore the extraordinary and/or unusual stable cluster units within the series, the energy gain (ΔE) has been evaluated which reveals Cd3O3 as magically stable cluster among the entire series of CdnXm (n, m = 1–3, X = O, S, Se, Te). Analysis of the frontier molecular orbitals suggests that electron transport is easily facilitated inside the Cd3O3 cluster system. The optical absorption spectra provide evidence that the Cd3O3 cluster is active in the visible range (λ = 472.4 Å) of the electromagnetic spectrum. The origin of the vibrational properties, especially for the visibly active Cd3O3 is addressed through critical study on its infrared spectra, which in turn, will provide experimentalists with valuable insights for its potential synthesis and innovative applications in the domain of optical applications as its assembled materials.