ABSTRACT
The first organic molecular representation was developed by Couper to represent glucose, oxalic acid, and other organic molecules. The bond-line formula is a handy way to represent organic molecules, mainly with long-chained skeleton. It is also the usual formula to represent molecules in a mechanism. The stick-and ball model is widely used to represent optimized molecules theoretically. The partial atomic charge is also dependent upon the method and/or the basis set to obtain the wave function. In carbon monoxide, the negative charge is located at the oxygen atom as expected since it is more electronegative than the carbon atom. One of the most appropriate methods for calculating partial atomic charges for molecules is QTAIM atomic charge. The dashed-wedged line notation can be a variation of the bond line formula when representing branched molecules by using same zig-zag line to represent the carbon chain and dashed-wedged bonds to represent the branch.
