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The following function has a bug

def kramers_kronig_trans(diele_func_imag: np.array,
                         energies: List[float],
                         ita: float = 0.01) -> np.ndarray:
    mesh = energies[1] - energies[0]
    result = []
    ee2ss = [[e ** 2 - energy_grid ** 2 for e in energies]
             for energy_grid in energies]
    for imag_idx in range(6):
        imags = diele_func_imag[:, imag_idx]
        inner_result = []
        for ee2s in ee2ss:
            integrals = [e * imag * ee2 / (ee2 ** 2 + ita ** 2)
                         for e, ee2, imag in zip(energies, ee2s, imags)]
            inner_result.append(1 + sum(integrals) * mesh * 2 / pi)

        result.append(inner_result)

    return np.array(result).T

According to vise commands and “Commands for creating inputs” in Wiki, I tried evaluating the dielectric tensors in some insulating oxides.
Some approximations for evaluating dielectric tensors were tried, including the random phase approximation (RPA).

The values in cubic systems were comparable to those reported previously.
Meanwhile, for example, in monoclinic systems (ZrO2, HfO2, Bi2O3), OUTCAR files showed the positive sign of ε(13) components although their negative signs were reported in a Prof. Kumagai’s article and other articles.
https://journals.aps.org/prb/abstract/10.1103/PhysRevB.89.195205
This difference in the sign of components seems not to be related to XC functionals.

Below is an example that was obtained in my calculation for monoclinic HfO2.
･ VASP version: 5.4.4
･ XC functional: PBEsol
･ Ecut = 520 eV
･ k-points mesh: 10 * 10 * 10
･ Origin in BZ sampling: (0.5, 0.5, 0.5), gamma-centered mesh

MACROSCOPIC STATIC DIELECTRIC TENSOR (including local field effects in DFT)

       4.979547     0.000000     0.140013
       0.000000     5.001772     0.000000
       0.140012     0.000000     4.693212

I would appreciate it if someone would tell me why this difference appears and what calculation processes/conditions are needed to obtain correct dielectric tensors.

When the command "vise vs -t band" is entered, to my knowlege, the following message will be displayed:
INFO: Numbers of kpoints are incremented to be even numbers.

1. What is the effect/reason of this treatment?

2. Would it be a problem to rewrite non-zero-weighted k points created in a vise command with those written in a IBZKPT file in a previous SCF calculation?
   In my calculations, band-structure caluculations are performed self-consistently;
   a WAVECAR file converged in a previous run is read, and an ICHARG tag is NOT set.

It would be better if the number of bands for band structure calculations and DOS is changed depending on ISPIN

I have fundamental questions on the DOS plotter implemented in vise.

According to "Tutorial – Calculations of various properties" in the vise homepage,
https://kumagai-group.github.io/vise/tutorial_properties.html
to my knowledge, the default command "vise pd" creates a total DOS plot and LDOS plots distinguished by their Wychoff positions.
In addition, color-coded PDOS are also plotted.

Is it possible to do the following three treatments in our command line?

1. Combine LDOS as one plot per element.
   For example, for a Na-containing cell with three Wychoff positions of Na, is there a command to create a "summarized" Na LDOS plot?

2. Change the "Energy (eV)" range and the "Dos (1/eV)" range.
   For example, is there a command to extend the lower limit of the energy range from -5 to -10?

3. Clear the legends (or change their positions) in a DOS plot.