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Dear all,</div>
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I would like to evaluate the magnetic dipole matrix L_mn = < m | L | n > using QE. </div>
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Relevant routines are in orbm_kubo.f90 which implements the orbital magnetization</div>
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\sum_n < n | L | n > using the berry phase method (<span style="color: rgb(85, 85, 85); font-family: "Proxima Nova", "Helvetica Neue", Helvetica, Helvetica, Arial, sans-serif; font-size: 1.14286rem;"><span style="font-size: 11pt; line-height: normal; font-family: Arial, Helvetica, sans-serif;">Phys.
Rev. B</span><span style="font-size: 11pt; line-height: normal; font-family: Arial, Helvetica, sans-serif;"> </span><span style="font-size: 11pt; line-height: normal;"><span style="box-sizing: border-box; line-height: normal; font-family: Arial, Helvetica, sans-serif;">74</span></span><span style="font-size: 11pt; line-height: normal; font-family: Arial, Helvetica, sans-serif;">,
024408</span></span><span style="color: rgb(0, 0, 0); font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; background: var(--white);">). I managed </span><span style="color: rgb(0, 0, 0); font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; background: var(--white);"> </span></div>
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<span style="color: rgb(0, 0, 0); font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; background: var(--white);">to modify the code to print out L_mn. However, I noticed that those m, n are all occupied </span></div>
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<span style="color: rgb(0, 0, 0); font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; background: var(--white);">bands and the implemented finite difference method to calculated the derivative of the </span></div>
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<span style="color: rgb(0, 0, 0); font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; background: var(--white);">bloch function is only valid for occupied bands. I'm wondering if it is possible to extend</span></div>
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<span style="color: rgb(0, 0, 0); font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; background: var(--white);">the method to include unoccupied bands.</span></div>
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<span style="color: rgb(0, 0, 0); font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; background: var(--white);">Best,</span></div>
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<div style="font-family:Tahoma; font-size:13px">Xiaoming Wang
<div>Postdoctoral Research Associate</div>
<div>Department of Physics and Astronomy</div>
<div>University of Toledo</div>
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