Thanks Bruce.

I agree that the paper and the cif file had no relation. I merely wanted to emphasize the point that ATOMS was giving an erroneous output.  

Cheers,

Kaustubh

Sent from Mail for Windows 10

From: Bruce Ravel
Sent: Tuesday, February 27, 2018 10:54 PM
To: XAFS Analysis using Ifeffit
Subject: Re: [Ifeffit] Error in Atoms output

On 02/19/2018 06:23 AM, Kaustubh Priolkar wrote:

> We are trying to fit low temperature V K edge EXAFS data in V2O3. As per

> the cif files available (attached herewith – V2O3_10K data.cif) the

> structure is described by I2/a space group. When this file is read by

> ATOMS it gives an erroneous output ( attached herewith - feff.inp). In

> particular the values of V-O and V-V bond distances are not correct and

> do not match with bond distances reported in literature (Phys. Rev. B 2

> (1970) 3771).

>

> Could anyone tell me where am I making a mistake. I am aware that I2/a

> is a non standard space group but I am not sure if I need to take any

> precaution while reading the cif file in ATOMS.

>

> Thanks and regards,

Hi Kaustubh,

Thanks for this bug report.  This uncovered not one but two bugs in how

Atoms handles monoclinic space groups.  How economical!  I will be

pushing a fix to github soon and I will try to find some time to make a

new windows installer.

I should point out that, even with the bug fix, the distances using the

CIF file you attached will not match Phys. Rev. B 2 (1970) 3771.

The CIF file that you supplied is from

doi:10.1016/S0022-4596(03)00295-0, which reports slightly different

numbers for the undoped V2O3 compared to the 1970 paper.  I have

attached a feff.inp file that I think is correct.

B

--

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  National Institute of Standards and Technology

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