Rimsha BaloachSP19-R06-005Prof. Anila AsifLHR TP 65092026-02-192020-02-19https://repository.cuilahore.edu.pk/handle/123456789/1921Nonlinear optical materials possess high rank in fields of optics owing to their impacts and utilization and extend their applications in industrial sector as well. 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. This inquiry adds 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 and then these electrons contribute towards the formation of new HOMO as a result reduction in energy gap is observed. This lowering of HOMO-LUMO gap ranges from 0.63eV to 3.69eV. These excesses of electrons also come up with the increased hyperpolarizability values of complexes 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 in support of our obtained results. Non covalent interaction (NCI) along with quantum theory of the atoms in molecules (QTAIM) analysis was carried out to better understand the bonding interactions between alkali metal atoms and B12P12 nanocage. All the results thus obtained consider these bi-alkali metal doped nanocages as exceptional thermodynamic stable materials with improved NLO response and make these complexes superb candidates for their vast approach in optics.enDepartment of ChemistryChemistrySP19Prof. Anila AsifDFT Investigationbi-Metal DopingB12P12 NanocageNonlinearThesis