Trouble with lj units

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Hi @Akshay_Chauhan,

A few comments I can make:

  1. You can make your formula more readable by enclosing your LaTeX writing in $ symbols. There is a LaTeX interpreter on the forum
  2. The Bjerrum length formula is: \lambda_B = e^2/(4 \pi \epsilon_0 \epsilon_r k_B T)., notice that it does not depend on the units you use. You could compute it using some units and divide it using your unit scale to get the LJ value, that’s the easiest way. However I think your reasoning is incorrect, k_B is set to 1 in LJ units, but T and \epsilon_0 also have values to scale, and \epsilon_r (the dielectric constant) depends on your medium. But that’s not the parameter I would try to modify first as electrostatic interactions are generally simulated in vacuum, with \epsilon_r=1. Other values are for implicit solvent and other specific cases. With this in mind, I think your formula in reduced units is incorrect (and non-homogeneous to a length).
  3. What do you mean when you say “The paper I’m currently trying to reproduce have set their Bjerrum Length to be 3 \sigma”? What are you trying to simulate? This is not something that we can guess from the informations you provide.
  4. You mention some part of the dielectric command manual page. Please state when you do so. Your statement is a bit confusing.
  5. This is unrelated to your previous issues with LJ units. You should start a more detailed thread next time stating exactly your specific problem.