UROP Proceedings 2021-22

School of Science Department of Physics 60 Monte Carlo Simulation of 2D Supramolecular Assembly Supervisor: LIN Nian / PHYS Student: WENG Chun Yu / IRE Course: UROP1000, Summer In this report, the molecular assembly of v-shape molecule on a 2D plane is simulated using Kinetic Monte Carlo method to produce hexagonal structures. First, the theory of the simulation and the master equation of the algorithm would be briefly discussed. Then, the practical choices of equations used in program would be explained. After discussing the theory, several important simulation results would be shown to study the effects of different physical parameters on the yield, including diffusion energy, bond energy, rotational bond energy, temperature, and the concentration of molecules. Finally, the simulation data would be analysed to provide some generalisations. Organic Molecular Beam Deposition in Ultra-high Vacuum Supervisor: LIN Nian / PHYS Student: KURNIAWAN Michael Alexander / PHYS Course: UROP1100, Spring With the emergence of various novel properties such as tunability of band gaps of 2D Metal Organic Frameworks (2D-MOFs), studying its band structure will aid the development for their usage in modern technology. This work thus attempts to simulate the band structure and the total density of states of 2DMOFs with Honeycomb-Kagome lattice arrangement using MATLAB program. Band gap calculation are performed with varying values of potential and two different radiuses of the metal atoms which shows larger gaps with increasing potential while there is an unexpected decrease of band gap in certain values of range with the atom having radius of 0.2 nm which could stem from the affected organic ligand potential with the larger metal atom’s radius. Organic Molecular Beam Deposition in Ultra-high Vacuum Supervisor: LIN Nian / PHYS Student: LI Hengjian / SSCI ZHANG Xiangxi / IRE Course: UROP1000, Summer UROP1100, Summer The project aims to discover the minimum evaporation temperature for two types of molecules: Fe-PC and (NH2)8Ni-PC. The experiment method is organic molecular-beam epitaxy which takes place in the vacuum produced by two vacuum pumps. Molecules were heated to different temperatures to generate a molecular beam. The melting point of the Fe-Pc molecule is between 250°C and 270°C; the intact molecule can be successfully deposited on the substrate plate. But the (NH2)8Ni-PC molecule cannot deposit successfully. In the future, new components can be added to the chamber to enhance the efficiency and accuracy, and other molecules can also be studied using this method.