Re: [Ifeffit] Linear Combination Fitting using ATHENA

[Teck Kwang Choo]

That's magnetite unfortunately!


On 12 August 2013 14:02, Scott Calvin  wrote:

> Yes it does, Teck Kwang:
> http://millenia.cars.aps.anl.gov/cgi-bin/newville/Model-Search.cgi/ModelData/fe3o4_rt01_mar02.xmu
>
> --Scott Calvin
> Sarah Lawrence College
>
> On Aug 11, 2013, at 11:12 PM, Teck Kwang Choo  > wrote:
>
> The database: http://cars.uchicago.edu/~newville/ModelLib/search.html<
> http://cars.uchicago.edu/%7Enewville/ModelLib/search.html> does not seem
> to have Ferrite.
>
> The matrix of my sample is largely Mg-ferrite where Fe is in the form of
> Fe (III). If you anyone has the spectra for Mg-ferrite, would it be
> possible to provide it to me? Otherwise, I do not think my sample spectra
> would be useable at all!
>
> Thanks and kind regards.
>
>
> On 10 August 2013 02:21, Matthew Marcus  mamar...@lbl.gov>> wrote:
> I would guess that you need better standards.  In particular, FeO is not
> your typical Fe(II) mineral or oxide.  What is the system you're working on?
> I have an extensive collection of Fe XANES reference spectra, including a
> number of Fe(II) species.
>
> LCF gives you the fraction of Fe atoms included in the sample.  For
> example, suppose you had a sample which was genuinely a mix representable
> as FeO.Fe2O3.  Then, LCF would properly report 2/3 Fe2O3 + 1/3 FeO because
> 2/3 of the Fe atoms are in the Fe2O3 fraction.
> mam
>
>
> On 8/8/2013 8:37 PM, Teck Kwang Choo wrote:
> Hello,
>
> I have been using ATHENA to perform Linear Combination Fitting (LCF) on my
> XANES spectrum to quantify the amounts of Fe (II) and Fe (III) in my
> samples using only FeO and Fe2O3 as standards. The results showed a
> majority of Fe (II), which is contrary to what was expected.
>
> This made me wonder if the LCF results from XANES is a molar percentage
> (mol %) or weight percentage (wt%).
>
> Could anyone enlighten me on this matter?
>
> Thanks!
>
> --
> Teck Kwang Choo
> PhD Student
> Department of Chemical Engineering
> Room 225, Building 36
> Monash University
> Mobile No.: 04-11489904
>
>
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>
>
> --
> Teck Kwang Choo
> PhD Student
> Department of Chemical Engineering
> Room 225, Building 36
> Monash University
> Mobile No.: 04-11489904
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-- 
Teck Kwang Choo
PhD Student
Department of Chemical Engineering
Room 225, Building 36
Monash University
Mobile No.: 04-11489904
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Re: [Ifeffit] Linear Combination Fitting using ATHENA

[Teck Kwang Choo]

The database: http://cars.uchicago.edu/~newville/ModelLib/search.html does
not seem to have Ferrite.

The matrix of my sample is largely Mg-ferrite where Fe is in the form of Fe
(III). If you anyone has the spectra for Mg-ferrite, would it be possible
to provide it to me? Otherwise, I do not think my sample spectra would be
useable at all!

Thanks and kind regards.


On 10 August 2013 02:21, Matthew Marcus  wrote:

> I would guess that you need better standards.  In particular, FeO is not
> your typical Fe(II) mineral or oxide.  What is the system you're working on?
> I have an extensive collection of Fe XANES reference spectra, including a
> number of Fe(II) species.
>
> LCF gives you the fraction of Fe atoms included in the sample.  For
> example, suppose you had a sample which was genuinely a mix representable
> as FeO.Fe2O3.  Then, LCF would properly report 2/3 Fe2O3 + 1/3 FeO because
> 2/3 of the Fe atoms are in the Fe2O3 fraction.
> mam
>
>
> On 8/8/2013 8:37 PM, Teck Kwang Choo wrote:
>
>> Hello,
>>
>> I have been using ATHENA to perform Linear Combination Fitting (LCF) on
>> my XANES spectrum to quantify the amounts of Fe (II) and Fe (III) in my
>> samples using only FeO and Fe2O3 as standards. The results showed a
>> majority of Fe (II), which is contrary to what was expected.
>>
>> This made me wonder if the LCF results from XANES is a molar percentage
>> (mol %) or weight percentage (wt%).
>>
>> Could anyone enlighten me on this matter?
>>
>> Thanks!
>>
>> --
>> Teck Kwang Choo
>> PhD Student
>> Department of Chemical Engineering
>> Room 225, Building 36
>> Monash University
>> Mobile No.: 04-11489904
>>
>>
>> __**_
>> Ifeffit mailing list
>> ifef...@millenia.cars.aps.anl.**gov 
>> http://millenia.cars.aps.anl.**gov/mailman/listinfo/ifeffit
>>
>>  __**_
> Ifeffit mailing list
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> http://millenia.cars.aps.anl.**gov/mailman/listinfo/ifeffit
>



-- 
Teck Kwang Choo
PhD Student
Department of Chemical Engineering
Room 225, Building 36
Monash University
Mobile No.: 04-11489904
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