# DFT Vasp calculation not converging when doing a SCF calculation for monolayer MoS2 [closed]

I am trying to calculate the electronic structure of Monolayer Molybdenum Disulfide ($$\ce{MoS_2}$$) using Vasp. However, I encounter problems with convergence. It does not seem that my calculations converge at all. I am using a Monkhorst Pack grid 15 * 15 * 1 (although I tried different densities to understand if this would influence convergence).

In the POSCAR file, I start with the bulk POSCAR file available on materialsproject.org and I increase the length of the vector "c" pointing from one layer to its neighbor. Regarding the INCAR parameters, I just use ISMEAR = 0 , SIGMA = 0.2 , ENCUT = 500 , PREC = Accurate. I'm still learning Vasp and more generally matter simulation and CMT, so I do not fully understand what many of the INCAR parameters do. Therefore, my INCAR file is quite simple.

My question is: what is the underlying reason for this non-convergence when modeling a monolayer $$\ce{MoS2}$$ system and how to avoid it?

Thanks

• @Phy +1 But can you show the input and output files in a code block? If the output file is too long you can upload it here in a folder called 6433 since you can see in the URL of this question the number 6433, which is the ID number for this question. Jul 31 at 0:48