# Monolayer

The material system consists of 16 two-dimensional self-assembled molecules (or chains) of alkanethiols ${\displaystyle CH_{3}(CH_{2})_{n-1}SH}$, where n = 15 is the number of carbon atoms along the alkyl chain backbone, adsorbed onto a gold (Au) substrate. The molecular basis of stress and strain is illustrated through changes in the potential energy surface due to an external perturbation, viz., compressive load. Molecular dynamics has been used to simulate the self-assembled monolayer under zero-stress and under an external load by a flat surface (wall). Module changeable parameters include the type of corrugation potential (harmonic or sinusoidal), configurations of the molecules, number of molecules (1, 2 or 4) per unit cell, and temperature. Data that can be obtained from the module are numerous and include conformation and configuration parameters of the assembling molecules, total energy during loading, tilt angle of the loaded molecules, total force, displacement, etc. Numerous plots are generated and include energy versus time and molecule tilt angle versus time, energy versus tilt, and energy versus strain. The Young modulus and toughness of the organic assembly can be derived and their respective sensitivity to various parameters can be assessed. The results of the simulation can also be compared with data from atomic force microscopy/interfacial force microscopy (AFM/IFM) measurements.