Mechanical properties graphene nanoribbons

[anahita]

Hi
In calculation the mechanical properties of graphene nanoribbons by tight binding methods should band structure graphene calculated by the DFT and tight binding methods fitted to calculate b parameter. In the tight binding methods hopping parameter changes as follow:
t'_{ppsigma}=t_{ppsigma} exp(-b{l/a0 - 1)) .
Can help me for calculate b??

 

[eljose79]

Hello,

Thank you for your question. Calculating the b parameter in tight binding methods can be a complex process and it is important to have a strong understanding of the theory and methods involved. I can offer some general guidance, but it may be helpful to consult with a colleague or reference materials for more specific advice.

First, it is important to note that the b parameter is a fitting parameter used to adjust the hopping parameter (t'_{ppsigma}) in the tight binding method to better match the results from density functional theory (DFT) calculations. Therefore, the first step would be to perform DFT calculations on your system and obtain the band structure for graphene.

Next, you will need to choose a range of values for the b parameter and calculate the corresponding band structure using the tight binding method. This can be done using software packages such as VASP, Quantum Espresso, or TBTK. The calculated band structure can then be compared to the DFT results, and the b value that gives the best match between the two can be chosen.

It is important to note that the b parameter can vary for different systems and may need to be adjusted for different types of graphene nanoribbons. Additionally, the accuracy of the b parameter can also depend on the accuracy of the DFT calculations and the tight binding method used. Therefore, it may be necessary to perform multiple calculations and adjust the b value to find the best fit.

I hope this helps in your calculations. Best of luck with your research!