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Contents
Contents
PWscf
User's Guide (v.7.2)
Contents
1 Introduction
1.1 What can
PWscf
do
1.2 People
1.3 Terms of use
2 Compilation
3 Using
PWscf
3.1 Input data
3.2 Data files
3.3 Electronic structure calculations
3.3.0.1 Single-point (fixed-ion) SCF calculation
3.3.0.2 Band structure calculation
3.3.0.3 Noncollinear magnetization, spin-orbit interactions
3.3.0.4 DFT+U
3.3.0.5 Dispersion Interactions (DFT-D)
3.3.0.6 Hartree-Fock and Hybrid functionals
3.3.0.7 Dispersion interaction with non-local functional (vdW-DF)
3.3.0.8 Polarization via Berry Phase
3.3.0.9 Finite electric fields
3.3.0.10 Orbital magnetization
3.4 Optimization and dynamics
3.4.0.1 Structural optimization
3.4.0.2 Molecular Dynamics
3.4.0.3 Variable-cell optimization
3.4.0.4 Variable-cell molecular dynamics
3.5 Direct interface with
CASINO
3.5.0.1 Practicalities
3.5.0.2 How to generate
xwfn.data
files with
PWscf
3.6 Socket interface with i-PI
3.6.0.1 Practicalities
3.6.0.2 How to use the i-PI inteface
3.6.0.3 Advanced i-PI usage
4 Performances
4.1 Execution time
4.2 Memory requirements
4.3 File space requirements
4.4 Parallelization issues
4.5 Understanding the time report
4.5.1 Serial execution
4.5.2 Parallel execution
4.5.2.1 Quick estimate of parallelization parameters
4.5.2.2 Automatic guess of parallelization parameters
4.5.2.3 Typical symptoms of bad/inadequate parallelization
4.6 Restarting
4.6.1 Signal trapping (experimental!)
5 Troubleshooting
5.0.0.1 pw.x says 'error while loading shared libraries' or 'cannot open shared object file' and does not start
5.0.0.2 errors in examples with parallel execution
5.0.0.3 pw.x prints the first few lines and then nothing happens (parallel execution)
5.0.0.4 pw.x stops with error while reading data
5.0.0.5 pw.x mumbles something like
cannot recover
or
error reading recover file
5.0.0.6 pw.x stops with
inconsistent DFT
error
5.0.0.7 pw.x stops with error in cdiaghg or rdiaghg
5.0.0.8 pw.x crashes with no error message at all
5.0.0.9 pw.x crashes with
segmentation fault
or similarly obscure messages
5.0.0.10 pw.x works for simple systems, but not for large systems or whenever more RAM is needed
5.0.0.11 pw.x crashes with
error in davcio
5.0.0.12 pw.x crashes in parallel execution with an obscure message related to MPI errors
5.0.0.13 pw.x stops with error message
the system is metallic, specify occupations
5.0.0.14 pw.x stops with
internal error: cannot bracket Ef
5.0.0.15 pw.x yields
internal error: cannot bracket Ef
message but does not stop
5.0.0.16 pw.x runs but nothing happens
5.0.0.17 pw.x yields weird results
5.0.0.18 FFT grid is machine-dependent
5.0.0.19 pw.x does not find all the symmetries you expected
5.0.0.20 Self-consistency is slow or does not converge at all
5.0.0.21 I do not get the same results in different machines!
5.0.0.22 Execution time is time-dependent!
5.0.0.23
Warning : N eigenvectors not converged
5.0.0.24
Warning : negative or imaginary charge...
, or
...core charge ...
, or
npt with rhoup< 0...
or
rho dw< 0...
5.0.0.25 Structural optimization is slow or does not converge or ends with a mysterious bfgs error
5.0.0.26 pw.x stops during variable-cell optimization in checkallsym with
non orthogonal operation
error
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