units of E_DENSITY_CUBE

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Claudio

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Mar 17, 2011, 4:40:07 PM3/17/11
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Dear all, I can't find in the manual what the units are for the
electronic density in the cube file. Is it electrons/A^3, if not how
do I tell from output or specify this on input?

Thanks,
Claudio

Campomanes Ramos Pablo

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Mar 17, 2011, 5:19:19 PM3/17/11
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Dear Claudio,

if other units are not specified in the input reference, atomic units are used.

Regards,
Pablo.

________________________________________
From: cp...@googlegroups.com [cp...@googlegroups.com] on behalf of Claudio [marg...@gmail.com]
Sent: Thursday, March 17, 2011 9:40 PM
To: cp2k
Subject: [CP2K:3147] units of E_DENSITY_CUBE

Thanks,
Claudio

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Claudio

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Mar 17, 2011, 8:31:58 PM3/17/11
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Pablo, thanks for the reply. I am still unclear though ...
I never specify any units in my input file however when I input the
coordinates under

&SUBSYS
&CELL
ABC xx yy zz
ALPHA_BETA_GAMMA aa bb gg
PERIODIC XYZ
&END CELL
&COORD
<my coordinates>

they are correctly interpreted as being in A. I know this because the
output file reads:

<my coordinates>
UNIT angstrom
SCALED F
&END COORD


Therefore, I do not know what units are being used in the cube file. I
can clearly open the cube file in something like VMD and it seems like
things should be in A (bond lengths are what one would expect in A
anyway). However I am unclear about the units of the density.

I am not sure if my email is totally clear, I can try again if it is
not.

Thanks for your help!





On Mar 17, 4:19 pm, Campomanes Ramos Pablo <pablo.campoma...@epfl.ch>
wrote:
> Dear Claudio,
>
> if other units are not specified in the input reference, atomic units are used.
>
> Regards,
> Pablo.
>
> ________________________________________
> From: cp...@googlegroups.com [cp...@googlegroups.com] on behalf of Claudio [margul...@gmail.com]

Teodoro Laino

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Mar 18, 2011, 3:06:26 AM3/18/11
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the units of the density are atomic units of electron density.
coordinates are in angstrom.

Campomanes Ramos Pablo

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Mar 18, 2011, 3:17:05 AM3/18/11
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Dear Claudio,

if "Default unit" is not explicitly specified in the CP2K input reference for a given keyword, the default units that the code will use are atomic units.

If you read _carefully_ the manual, you will see that default units for ABC are angstroms. Then, with this input file, you will have ABC in angstroms and E_DENSITY_CUBE in atomic units.

Regards,

Pablo.

________________________________________
From: cp...@googlegroups.com [cp...@googlegroups.com] on behalf of Claudio [marg...@gmail.com]
Sent: Friday, March 18, 2011 1:31 AM
To: cp2k
Subject: [CP2K:3149] Re: units of E_DENSITY_CUBE

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