[DFTB-Plus-User] Transport calculation problem for defining the geometry

[bedamani singh]

dear DFTB users,
I have optimized a whole system (device and two contacts having two
principal layers) and then tried for the transport calculation. But an
error "contact 1 is not parallel with any of the axis" comes up.  Since the
optimized structure may or may not be perfectly symmetric, the two
principal layers in the contacts may or may not be the exact replica of
each other. Hence for the transport calculations, is it necessary to
optimize the system as a whole? Or can we optimize the contacts separately
and afterwards join with the device?


I have tried with the following input files (dftb_in.hsd and geo.gen), and
it always gives error like
"-> Contact 1 does not consist of two rigidly shifted layers"

so how to I get rid of this error? any kind of help is highly appreciated

 bedamani
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