Dear Sir,
I did not understand the first part (cell) of your question. I will be really grateful if you could kindly elaborate on that.
If you are trying to do quantum calculations on three or four molecules, the first step will be to figure out their lowest energy configuration. The idea is to arrange all these 3-4 molecules in all possible orientations relative to each other and then optimize them separately. After optimization, we can compare their energies and see which one is the lowest (most negative energy). That will be the ground state.
For example, I have attached a figure that shows some of the optimized configurations of cationic water cluster [(H2O)6+] composed of six water molecule (Original paper: Article Electron Detachment and Subsequent Structural Changes of Wat...
)For a small number of simple molecules, it is possible to figure out all the possible configurations. However, for a large number of molecules or for molecules with complex structures, we may need some automated algorithms that can generate all possible configurations.
For the molecule only . You gave in the fig. In which the command for Gaussian 09w is important . What type of command
In short, to submit the calculation in Gaussian09, we need to first prepare an input file (e.g, input.gjf or .com) that will contain the coordinate of the molecule along with the Keywords that are needed for the calculations. The input file can be generated manually or using some graphical user interface e.g., Gaussview, Avogardo, etc. Once the input file is ready we need to submit the input file to Gaussian for calculation by a simple command, e.g., g09 input.gif (which can also be submitted directly from the GUI,). After the calculation finishes, we can open the output file for results for checking. I have attached an example input file for H2O dimer optimization. Further tutorials are given here: https://gaussian.com/videos/
- Badges
- Science topic
- Similar topics
- Control Systems Engineering
- Filtering