Dear PWSCF users and developers, I have been trying to do the conductance calculation for the twin boundary of Cu. I compared my results with previously done calculations and for most K points the transmission coefficients match up very well. But there are some k points that I get transmission coefficients more than 1! This is not reasonable, as the maximum value of transmission coefficient could be 1.I am getting 1.000345, and similar for other k points. Do you think transmission coefficients being more than 1 is just numerical error of the code or there is something wrong with my input file? Attached is the input file for lead and scatterign region -
SCF for the LEFT lead- &control calculation='scf' pseudo_dir = '/home/manoj/espresso-4.0.1/pseudo', outdir='./', prefix='lcu', / &system ibrav =0, celldm(1)=4.82, nat= 3, ntyp= 1, ecutwfc =150.0, occupations='smearing', smearing='gaussian', degauss=0.02, ecutrho=500 / &electrons conv_thr = 1.0e-8 mixing_beta=0.7 / ATOMIC_SPECIES Cu 63.55 Cu.pz-d-rrkjus.UPF ATOMIC_POSITIONS Cu 0.0 0.0 0.0 Cu -0.5 0.288675134 0.81649658 Cu -1.0 0.577350269 1.632993162 K_POINTS (automatic) 6 6 8 1 1 1 CELL_PARAMETERS {hexagonal} 1.0 0.0 0.0 -0.5 0.8660254037844386 0.0 0.0 0.0 2.449489743 >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> SCF for the RIGHT lead- &control calculation='scf' pseudo_dir = '/home/manoj/espresso-4.0.1/pseudo', outdir='./', prefix='rcu', / &system ibrav =0, celldm(1)=4.82, nat= 3, ntyp= 1, ecutwfc =150.0, occupations='smearing', smearing='gaussian', degauss=0.02, ecutrho=500 / &electrons conv_thr = 1.0e-8 mixing_beta=0.7 / ATOMIC_SPECIES Cu 63.55 Cu.pz-d-rrkjus.UPF ATOMIC_POSITIONS Cu 0.0 0.0 0.0 Cu 0.5 -0.288675134 0.81649658 Cu 1.0 -0.577350269 1.632993162 K_POINTS (automatic) 6 6 8 1 1 1 CELL_PARAMETERS {hexagonal} 1.0 0.0 0.0 -0.5 0.8660254037844386 0.0 0.0 0.0 2.449489743 >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> SCF for SCATTERING region- &control calculation='scf' pseudo_dir = '/home/manoj/espresso-4.0.1/pseudo', outdir='./', prefix='scu', / &system ibrav =0, celldm(1)=4.82, nat= 12, ntyp= 1, ecutwfc =150.0, occupations='smearing', smearing='gaussian', degauss=0.02, ecutrho=500 / &electrons conv_thr = 1.0e-8 mixing_beta=0.7 / ATOMIC_SPECIES Cu 63.55 Cu.pz-d-rrkjus.UPF ATOMIC_POSITIONS Cu 0.0 0.0 0.0 Cu -0.5 0.288675134 0.816496581 Cu -1.0 0.577350269 1.632993162 Cu -0.5 0.288675134 2.449489743 Cu 0.0 0.0 3.265986324 Cu 0.5 -0.288675134 4.082482905 Cu 1.0 -0.577350269 4.898979486 Cu 1.5 -0.866025404 5.715476066 Cu 2.0 -1.154700538 6.531972647 Cu 1.5 -0.866025404 7.348469228 Cu 1.0 -0.577350269 8.164965809 Cu 0.5 -0.288675134 8.981462390 K_POINTS (automatic) 6 6 4 1 1 1 CELL_PARAMETERS {hexagonal} 1.0 0.0 0.0 -0.5 0.866025403 0.0 0.0 0.0 9.797958971 >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> input file for conductance part- &inputcond outdir='./' prefixs='scu' prefixl='lcu' prefixr='rcu' tran_file ='trans.twin' ikind=2 ecut2d=200 energy0=0.0 denergy=0.0 ewind=101.d0 epsproj=1.d-6 nz1=25 bds=3.265986324 / 6 0.5000000 -0.5000000 1 4.2584095E-17 0.5000000 1 0.250000000 0.0000000 1 0.1666667 0.1666667 1 -1.2775231E-16 -0.2500000 1 0.2500000 -0.2500001 1 1 0.0 Regards, Manoj Srivastava University of Florida, Gainesville, FL