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# System prepended metadata

title: Hackmd Day one

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Hackmd Day one 

## Overview and basics 

### Hands-On part 1
* For any question about this part please post here. 
    * git clone https://gitlab.com/QEF/material_ncc_czechia_qe_school
    * tar zxvf qe-7.3.1-ReleasePack.tar.gz
    * cd qe-7.3.1/
    * mkdir build
    * cd build/
    * cp ../../script_CMake .
    * sbatch script_CMake

* Eszter Makkos: If I wish to install QE on Karolina, is there any difference in steps?
    * yes, you need to enable GPU offload with cmake or autotool options. The list of cmake options for various clusters can be found here: https://gitlab.com/QEF/q-e/-/wikis/Developers/CMake-build-system ; we are adding the cmake options for Karolina too 
* Kameyab: What "&ELECTRONS" block represents?
    * In general everything associated to the scf cycle, and convergence of  electronic structure   (https://www.quantum-espresso.org/Doc/INPUT_PW.html#idm804)

* Tingqiang: What is the command "ssh -i ..." to login in the server?

    * ssh -i <yourkey> <yourusername>@barbora.it4i.cz

* Abdul: Can we run `pp.x` if we set `disk_io="nowf"` or `minimal` in the `scf` input instead of the default `low` to save disk space? 
  *  Only the tasks that do not read the wave functions can in principle  work. But I am not sure that wave-functions are not always searched. Other tasks will certainly  have issues; for example the plots of single orbital densities. 
    
## Densities, Potentials and Supercells
    
* Jan: what happens when you specify both starting_magnetization and tot_magnetization?
      
    * typically the code should complain, the two methods are mutually exclusive 
    
* Jan: is the magnetization of all atoms of a single species kept equal during the SCF cycles?
    
    * Unless the two atoms are symmetrically equivalent the magnetization is free to change during the scf



### Hands-On part 2 
