### Author Topic: The units of electrondensity in 1D projector  (Read 400 times)

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##### The units of electrondensity in 1D projector
« on: June 14, 2022, 14:19 »
Dears,
I calculated the electrondensity and ploted it in 1D projector along z axis (the attached picyure). I am confused now! I have two questions:
1- shouldn't be the units in (1/A^2) instead of (1/A^3) since I ploted it along an direction?
2- If I want to calculated the number of electrons from this data, I should calculate the area of below the graph? if not, how can I do it?
Thanks

#### Anders Blom

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##### Re: The units of electrondensity in 1D projector
« Reply #1 on: July 6, 2022, 06:33 »
No, the unit is correct, although I understand why you might think otherwise. It's not an integral over the perpendicular direction, just a sum or average. (And besides, if it were an integral, the new unit would be 1/Ang.)

To get the number of electrons you integrate over XYZ so once you already have the sum over XY, you just need to integrate over Z and normalize by the A/B plane area. That said, there are easier ways to get the total number of electrons - it's a constant integer anyway, unless this is a device which it doesn't look like.