Nonlinear optical materials possess high rank in fields of optics owing to their impacts, utilization and extended applications in industrial sector. Therefore, design of molecular systems with high nonlinear optical response along with high thermodynamic stability is a dire need of this era. Hence, the present study involves investigation of bi-alkali metal doped boron phosphide nanocages M2@B12P12 (M=Li, Na, K) in search of stable nonlinear optical materials.The investigation includes execution of geometrical and opto-electronic properties of complexes by means of density functional theory (DFT) computations. Bi-doped alkali metal atoms introduce excess of electrons in the host B12P12 nanocage. These electrons contribute towards the formation of new HOMO, thus reducing HOMO-LUMO gaps. The reduced HOMO-LUMO gap ranges from 0.63eV to 3.69eV. The diffused excess electrons also come up with increased hyperpolarizability values of complexes i.e. up to 4.0×10 4 au. TD-DFT calculations have been performed to examine crucial transition states and for UV-VIS analysis.IR and DOS spectra have been plotted to support our obtained results. Non covalent interaction (NCI) calculations along with quantum theory of the atoms in molecules (QTAIM) analysis were carried out to understand the bonding interactions between alkali metal atoms and B12P12 nanocage. All obtained results suggest bi-alkali metal doped nanocages as exceptionally stable materials with improved NLO response and superb candidates for their vast applications in optics.

Recent years have seen a rise in the importance of designing materials with large nonlinear optical (NLO) responses. Different compounds having large nonlinear optical responses are being extensively studied for their boundless applications in this field. Contributing to this, we are presenting here an attempt to design novel nonlinear optical materials. In this study, alkali metal-doped bicorannulenyl (C 40 H 38 ) compounds (Li@Bicora, Na@Bicora, and K@Bicora) are designed and computationally investigated by using DFT calculations. Thermodynamic stabilities of all complexes are evident from their binding energies. A prodigious first hyperpolarizability value is observed after doping the bicorannulenyl with alkali metals. A significantly enhanced hyperpolarizability value (β o = 2.68 × 10 6 au) is shown by isomer VII of K@Bicora. Other analyses, such as TDOS and PDOS, NBO, QTAIM and NCI, are also performed to investigate the contributions of various systems, charge transfer, and modes of interaction. Absorption analysis has confirmed the transparency in the UV region. This theoretical insight into NLO material's prodigious NLO response will serve as a springboard for novel ideas in this area.

Nonlinear optical materials possess high rank in fields of optics owing to their impacts, utilization and extended applications in industrial sector. Therefore, design of molecular systems with high nonlinear optical response along with high thermodynamic stability is a dire need of this era. Hence, the present study involves investigation of bi-alkali metal doped boron phosphide nanocages M2@B12P12 (M = Li, Na, K) in search of stable nonlinear optical materials. The investigation includes execution of geometrical and opto-electronic properties of complexes by means of density functional theory (DFT) computations. Bi-doped alkali metal atoms introduce excess of electrons in the host B12P12 nanocage. These electrons contribute towards the formation of new HOMO, thus reducing HOMO-LUMO gaps. The reduced HOMO-LUMO gap ranges from 0.63eV to 3.69eV. The diffused excess electrons also come up with increased hyperpolarizability values of complexes i.e. up to 4.0×104au. TD-DFT calculations have been performed to examine crucial transition states and for UV-VIS analysis. IR and DOS spectra have been plotted to support our obtained results. Non covalent interaction (NCI) calculations along with quantum theory of the atoms in molecules (QTAIM) analysis were carried out to understand the bonding interactions between alkali metal atoms and B12P12 nanocage. All obtained results suggest bi-alkali metal doped nanocages as exceptionally stable materials with improved NLO response and superb candidates for their vast applications in optics.