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Hi all,</div>
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I want to calculate the spontaneous polarization of a 2D material using Berry Phase method. </div>
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However, I am facing some lacking in understanding the following issues.</div>
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<li>If gdir=3 (z-axis) and nppstr = 5, in this case it will take 5 k-points along z axis. However, for 2D materials kz should be 0. What does it mean by k string along reciprocal of z-axis. I tried with nppstr=1. The simulation fails.</li><li>What is the difference between the 'polarization calculated by iberry=.true' and electronic dipole calculated by lelfield=.true' ? Are they same?</li><li>What is the difference between electronic dipole and Ionic dipole reported during lelfield = .true calculation? </li></ol>
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Thanks in advance.</div>
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<b>Atanu K Saha</b></div>
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Ph.D. Candidate</div>
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ECE, Purdue University</div>
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