Re: [cclib-users] orbital occupation numbers

[Axel S. <axe...@go...>]

Hi Karol,

thank you! I just compared to my test files and yes, those are the numbers
that we want.

I will follow the progress on the development version to see when we can
use cclib for orbkit.

Cheers
Axel

On Thu, Oct 23, 2014 at 6:38 PM, Karol Langner <kar...@gm...>
wrote:

> I created an issue for this:
> https://github.com/cclib/cclib/issues/143
>
>
> On Thu, Oct 23, 2014 at 12:31 PM, Karol Langner <kar...@gm...>
> wrote:
>
>> Axel,
>>
>> The terminology seems to be a little tricky. To be specific, the NO
>> coefficients that we currently parse (for Gaussian) are those that define
>> the natural orbital as an eigenvector of the diagonalized density matrix.
>>
>> Here is an example of the output from out unit tests:
>>
>> https://github.com/cclib/cclib/blob/master/data/Gaussian/basicGaussian09/water_cis.log#L578
>>
>> The eigenvalues printed there, I think, are the occupoation numbers you
>> need (the population in each orbital), although in that particular case
>> some are negative (maybe because the basis set is so small?). Anyway, we
>> don't parse them, but we could of course, if that will be useful for you.
>>
>> Cheers,
>> Karol
>>
>> P.S. A new release of cclib (1.3) is coming out soon. Which version are
>> you using? In any case, this will not make it into 1.3, so you will need to
>> use the dev version from github.
>>
>>
>> On Thu, Oct 23, 2014 at 12:07 PM, Axel Schild <axe...@go...
>> > wrote:
>>
>>> Hi Karol,
>>>
>>> I suppose that NO coefficients and orbital occupation numbers are the
>>> same, i.e. they should be the diagonals of the diagonalized density
>>> matrix.For single-determinant methods they are 2 (or 1) and for
>>> multi-determinant methods they have some value between 0 and 2 (or 1).
>>>
>>> At least I cannot think of any other meaning of "NO coefficients", but I
>>> never heard that term so far.
>>>
>>> Thanks, I hope that this feature is available soon as it would be pretty
>>> nice to use cclib!
>>>
>>> Cheers
>>> Axel
>>>
>>> On Thu, Oct 23, 2014 at 2:18 PM, Karol Langner <kar...@gm...>
>>> wrote:
>>>
>>>> Hi Axel,
>>>>
>>>> The attribute nocoeffs parses NO coefficients, and only for Gaussian at
>>>> the moment, I believe. It could be easily extended to other programs,
>>>> assuming our test logfiles contain the data.
>>>>
>>>> If I understand correctly, occupation numbers can be calculated from
>>>> the NO coefficients. Is that correct?
>>>>
>>>> Cheers,
>>>> Karol
>>>>
>>>>
>>>> On Thu, Oct 23, 2014 at 3:40 AM, Axel Schild <
>>>> axe...@go...> wrote:
>>>>
>>>>> Hi,
>>>>>
>>>>> I'm one of the developers of orbkit (
>>>>> http://sourceforge.net/projects/orbkit). So far, we are using our own
>>>>> Molden, GAMESS US, Gaussian log-file/fchk-file, and WFN-file parser, but we
>>>>> thought about (also) using cclib to be able to read all the file formats
>>>>> that you support.
>>>>>
>>>>> However, we need orbital occupation numbers (like those of MCSCF
>>>>> orbitals or of natural orbitals).
>>>>>
>>>>> Is this the data that is stored in the variable <nocoeffs> in the
>>>>> development version? If so, will it be available for any other than the
>>>>> GAMESS and Gaussian parsers anytime soon? If not, is this feature planned
>>>>> to be included?
>>>>>
>>>>> Cheers
>>>>> Axel
>>>>>
>>>>>
>>>>> ------------------------------------------------------------------------------
>>>>>
>>>>> _______________________________________________
>>>>> cclib-users mailing list
>>>>> ccl...@li...
>>>>> https://lists.sourceforge.net/lists/listinfo/cclib-users
>>>>>
>>>>>
>>>>
>>>
>>
>