ello everyone,
I am currently performing a simple curve fit on bulk MoS2 using an atoms file
for crystalline MoS2. I've found that increasing k_min on my fit (e.g. from 2
to 4) improves the quality of the fit (R-factor from 0.028 to 0.009), but also
increases S02. If I use a large enough k_mi
Dear all,
I have a standard exafs spectrum of copper K-shell and everything looks as
expected (Chi(E), Chi(k), Chi(R), Chi(q) …) when using Demeter 0.9.21 .
However the phase spectrum of (Chi(q)) appears quite different to literature
(e.g. B.K. Teo, Inorganic Chemistry Concepts 9; Martens et
s 0.9). (2) When Fitting the Debye�CWaller
factor (ss) and coordination number (N), although I use "abs()" to make it to
be positive, but the fitting results still be negative. But I did not meet
these problems in the old version in Artemis 0.8.012. I am wondering that
whether coul
I don't think it's at all strange, Anatoly, and I think Matthew's
solution is the right one--it seems obvious in retrospect that the
parameter that Ifeffit should evaluate is 1/R, but apparently it
wasn't obvious to me on Friday. :)
As for obtaining N instead of R, t
Hi Scott,
Thanks a lot, you are a good fortune-teller. I have low-Z scatterers (oxygen)
and high-Z scatteres (Pt).
Best regards,
JA
Scott Calvin ha escrito:
> Hi Juan,
>
> They're consistent. The higher r-factor on the kwt-1 data might be a
> clue about how reliable part o
On 03/09/2017 05:15 AM, Victor Streltsov wrote:
3 data set refined to completion with sensible refined parameter, however,
R-factor for 3^rd data set is 1. (overall R for 3 data set is huge
too) and after-fit plot for 3^rd data set is missing, only experimental
one shown. I am using latest
=11563eV, Rbkg=1.3, kweight =1
To fit data
k -range = 3.0~13.5, R -range =2.3~13.5
1. fitting parameters
set macc = 0.0
set so2 = 0.89// reduction factor
guess ePt = 0.0 // energy shift
set npt1=1.0// the number of Pt (1.0 means 12&nb! sp; Pt
a
bles, and approximately 41.333
measurements Weights sum to 1: no Weights forced between 0 and 1: no Overall e0
shift used: yes Noise added to data: 0 R-factor = 0.0003537 Chi-square =
0.00815 Reduced chi-square = 0.858
.standard weight e0
Hi Matthias and Leandro,
Thank you very much for your reply.
I checked the DW-factor (MSRD) and found it also varies significantly
depending on Fit k-weight as follows.
kw amp ss
1 0.8145660 +/- 0.0486470 0.0073230 +/- 0.0005240
2 0.9230700 +/- 0.0673820
previous fit it will have
been overwritten by the newer fit. Some of the other info, such as
R-factor by k-weight seems to get overwritten too.
I just pushed a fix for this to github and posted new windows installer
candidates at
http://bruceravel.github.io/demeter/#windows
If you see any oth
el file
> attached).
> In the case of the single fit I get a R-factor of 2.0x10-3 whereas for the
> best fit from the combinations I got 1.8x10-3 (the weights of each
> standards are also different in both cases).
My answer is still the same.
It is quite possible that I am not unders
likes it. 5
imidazoles and 3 sulfurs and I have an R-factor of 0.2% every time.
If there is non standard multiple scattering that occurs in multiple
unrelated proteins from different organisms then we would have no idea
what this could be.
Thanks for your comments!
Carolyn Carr
Hi Gavin,
What are the uncertainties on the high S02 values?
Fluorescence is unlikely to be the culprit. While it can affect your
ability to normalize properly, you're unlikely to account for a factor
of 2 by normalization if the data is relatively decent. And self-
absorption ten
Hi Scott,
No my fault, I suffer from tl;dr itis. I didn't read beyond linear combination.
That said it still works:
Fitting Data as chi(k) from 3.000 to 12.000
fit done use k-weight = 2
Fit included 181 data points and 1 variable
R-factor = 0.209356
chi-square = 30.92638
reduce
there is a photoelectron spectrum showing the relative
intensity of Auger and Photopeaks. The secondaries are roughly a
factor of 100 more intense than the other contributions.
It is possible to measure both TEY and Auger electron yield (AEY) and
you will see that the AEY is more surface sensitiv
Hi Yanyun,
Good. So here's the procedure for a Hamilton test.
We're comparing the fit with S02 guessed to the one with S02 set to 0.90,
because that was your a priori best guess at S02.
I take the ratio of the first R-factor to the second. You didn't actually say
the R-factor f
one. For fits in R
space, epsilon_r is used as the weighting factor: For a single data
set, the quantity minimized in the best fit is
chi_square = (1 / N ) Sum_i=1^N { [Data_i - Fit_i]^2 / epsilon_r^2 }
where the sum is over N R-space points. The data spacing for chi(R)
is set by the Fo
ed to firstly obtain the (short-ranged) lattice parameter
> (in angstrom) of each phase from an EXAFS fitting with an R-factor less
> than 0.02.
> Then the volume (in angstrom cube) of the unit cell of each phase is
> known. Given that the number of Co atoms /unit cell is known for each
>
very, very noisy data. Including C in the fit
might very well improve the fit in the sense of an R-factor--maybe, in
fact, there's a 45% chance of a modest improvement with a given set of
very noisy data, even if there's no C present. That does not mean that
a result like tha
Hi Mike,
On Sun, Dec 2, 2012 at 11:54 AM, Michael Morrill
wrote:
> Hello everyone,
>
> I am currently performing a simple curve fit on bulk MoS2 using an atoms file
> for crystalline MoS2. I've found that increasing k_min on my fit (e.g. from 2
> to 4) improves the quality
measurement you are
making (transmission, fluorescence). All of these factors can masquerade
a amplitude reduction factor.
What I do in practice is to measure a standard which has the same local
environment and fit the EXAFS with the known structure to extract an S02
which I then use
Hi Joselaine,
On Wed, Apr 24, 2019 at 8:40 PM Joselaine Cáceres gonzalez <
joselainecace...@gmail.com> wrote:
> Hi Matt, thank you for your answer!. The references I have about
> Malinowski´s work and some applications are:
>
> Malinowski, E.R., *Theory of error in factor ana
actly 0.0 with no fit taking place (enot = 0, amp = 0 (guess amp =
1) delr = 0 and ss = 0.003) and the R-factor of the fit is way over the
top (>10^20).
I've chosen a value of 0.5 for the 3rd and the 4th parameter just to see
if they're working and I was only doing a quick first
Hi all,
Scott answered my question about consistency but now I have a new doubt.
I have two fits (one in k1 and other in k3 weights) with fitted
parameters that have
uncertainty ranges overlaped, then... in principle, they are consitent,
right?
But the fit in k1 weight have a R-factor too high
to 0.005, my CN
jumps from 4.8 to 5.2.
When I make a cluster based on Yttria structure, I get DW factor of
0.008 +- 0.002, unrestrained. While I restrain the DW to 0.01, it
again jumps from 4.8 to 5.2.
First query...if you can pin down on the CN change (Carlo..you wanted
some numbers)
Second
Dear all,
Is there a physical limitation determining exafs bond distance resolution?
Very often the equation r = pi / 2 deltak is quoted as a measure for
bond distance resolution. But as i understand this equation is related
to the fourier transform traditionally used for exafs analysis.
If
myself and someone can correct me:
Certainly not all of my, say 10 reference spektra, are that similar that
I can get several LCFs with the same say R-factor. So, I will get some
clue to narrow the components. But still there can be, for example:
Standard-combi 1, 2, 3 equal to 1, 4, 6.
So,
my
(CdTiO3). No multiple
>> scattering paths used. The best fit goes something like this:
>>
>>
>> ********
>> Independent points = 13.166992187
>> Number of variables = 8.
you were hoping for.
>
> Regarding your Athena project, I suggest tweaking the position of E0
> and the k and R windows according to the advice provided in the links
> above. The experimental data looks nice and clean up to k~14.5 A-1.
>
> Best of luck,
> Leandro
>
&
means that the estimated
> uncertainties really aren't dependable for fits that are known to be bad
> (e.g. have a huge R-factor, unrealistic fitted parameters, etc.), but since
> those fits aren't generally the published ones, that's OK.
>
> Secondly, the high-
Dear Scott,
There are several papers dealing with effects of multielectron
photoexcitations present in atomic absorption background (AAB) of K and
L edge EXAFS spectra, which are responsible for the amplitude reduction
factor S02. A quantitative analysis of shake-up, shake-off and other
d it seemed
> a good fitting from the figure in Graphic window #1 - [Athena]. But the
> results showed that only path 1 had good values of N, R-factor,
> Chi-square, amp and sigma^2. If I choose only path 1 for fitting, the
> figure in Graphic window #1 - [Athena] showed only the highest
misleading. Lifetimes derived from
theory and experiment often differ by a factor of 2 or more. In the
transition metals of the first period plots of measured widths of the
L1(2s),L2(2p12), and L3(2p32) levels as a function of atomic number show
broad maxima which are not adequately described by theory
utside its
error bar. Also, the R factor for fit "B,D,E" is barely different from
those above, which further suggests that those two are not actually in
your sample.
What happens if you exclude those two from the combinatorial fit? Do
you see the same error message?
What happen
hi hiroshi,
i did not have a look at the attached project, but what paramteres did
you vary? even if you use different k-weightings, there is still the
strong correlation of N,S02 and the Debye-Waller like factor. so as long
as you do not keep two of these three on a certain value, your S02 might
er of variables : 0
Chi-square : 0
Reduced chi-square : 0
R-factor : 0
Measurement uncertainty (k) : 0
Measurement unc
_k for each data set.
> The two values are related and specifying either one is sufficient for
> the feffit() command to calculate the appropriate one. For fits in R
> space, epsilon_r is used as the weighting factor: For a single data
> set, the quantity minimized in the best fit is
t higher k than normal (perhaps 4 or 5 Ang^-1) or increasing the k-weight
used in the Fourier transform (perhaps to 3 or 4) would de-emphasize the
Se-Li scattering to a level that it was safe(r) to ignore.
FWIW, I would imagine that trying to fit coordination number or sigma^2 for
Se-Li at per
er-supplied value of epsilon_k
for fitting multiple dataset. If it is difficult to make the version
0.9.26 available soon, maybe in 0.9.25 there is a possibility to set
R-factor as a figure of merit for fitting rather than chi^2? That might
also help.
Thank you
All the best,
Kirill Lomachenk
minima. For Cobalt
and Nickel samples I typically get one or a few fits that are
obviously significantly better in R-factor (with reasonable distances,
sigma^2, etc) but for Zinc this is not the case.
I can get many good fits and Zinc likes to increase the coordination
up to 8 for all data sets I
Hi Ava,
Sorry for the trouble. It looks to me like the fit actually ran. Like,
getting non-trivial and non-starting values and uncertainties for 'ss_Cu1',
'dr_Cu1', etc tells me that many parts of the fit and code worked. I'm
not at all sure why Chi-square and R-f
in the data, the
> fit would indicate that C was present when it was not. That is *not* the
> same thing as saying there is a 77% chance of C being present.
>
> To see this, imagine very, very noisy data. Including C in the fit might
> very well improve the fit in the sense of an R-factor
ilar to the one reported in March 2018 under the
> topic "Athena (Demeter 0.9.26) does not import all datapoints from ascci
> file". However, the issue I am seeing always results in 1.2eV steps in
> the imported data. If my original file hast 0.3eV steps, the number of
> po
679339 10.5 0.090364699 11 0.092509939 11.5 0.108103081 There's a general trend of increasing epsilon_r with an increase in k. There's also a jump of a factor of 2 between 7.5 and 8. Why? Because there's a glitch there, and the glitch adds high-R structure.To make sur
parameters"
# -
# fitFoM R-factor
Reduced_chi-square Chi-square nvar nidp
'K4W(CN)8 R(1.7-6)'1 0.022714347.765
219223.767 30 45
'K4W(CN)8 R(1.7-4) no bkg' 3 0.
measurement you are making
(transmission, fluorescence). All of these factors can masquerade
a amplitude reduction factor.
What I do in practice is to measure a standard which has the same
local environment and fit the EXAFS with the known structure to
extract an
diffcult because the R factor of
the first 5 combinations with diffrent reference combinations is similar. And
as I see from my fitting the alignement plays really an important role on the
LCF. You know when I made allign marked groups based on the standard, it
alligns well the enregy but when I
04:44:48 2007
Subject: [Ifeffit] Exafs distance resolution
Dear all,
Is there a physical limitation determining exafs bond distance resolution?
Very often the equation r = pi / 2 deltak is quoted as a measure for
bond distance resolution. But as i understand this equation is related
to
eview version, but I was installing it only to
get the possibility to actually use the user-supplied value of epsilon_k
for fitting multiple dataset. If it is difficult to make the version
0.9.26 available soon, maybe in 0.9.25 there is a possibility to set
R-factor as a figure of merit for fitti
again all caps because this point is so
important that I want to yell it at you.
THE FOURIER TRANSFORM OF CHI(K) IS NOT A RADIAL DISTRIBUTION FUNCTION.
* chi(k) includes multiple scattering
* chi(k) includes a complex scattering factor
* For heavy elements, the magnitude of the complex sca
anticipation
Best
Pushkar
Independent points : 16.125
Number of variables : 4
Chi-square : 7324.9401796
Reduced chi-square : 604.118
R-factor: 0.0195782
Measurement uncertainty (k) : 0.0001264
Measurement uncertainty (R) : 0.0004142
inecace...@gmail.com> wrote:
>
>> Hi Matt, thank you for your answer!. The references I have about
>> Malinowski´s work and some applications are:
>>
>> Malinowski, E.R., *Theory of error in factor analysis.* Analytical
>> Chemistry, 1977. *49*(4): p. 606-612.
&g
first
two S subshells are so close to each other, my data can't identify them
(delr and ss) independently. So I defined their delr and ss to be same and
the
results match pretty well with the cubic phase. The r-factor and reduced-chi
square with the two models are very similar.Thanks a lot !
O
ly to account for a factor of 2 by
normalization if the data is relatively decent. And self-absorption tends to
suppress S02, not exaggerate it.
Why did you switch to fluorescence on just the handful of data sets? That might
provide us a clue.
--Scott Calvin
Sarah Lawrence College
On Jul 30,
lts in
the top of the results window: Later where a summary is usually shown it
is left blank:
R-factor for this data set = 0.46013
pathdegen amp sigma^2e0reff delta_RR
I started a n
of L, M, N, O, and P core levels with binding energies less
> than 1500 eV in approximately 25 elements. The results show that the
> framework provided by previously accepted theoretical estimates of
> lifetime broadening is sometimes misleading. Lifetimes derived from
> theory and
yed
> correctly for the most recent fit but, for the previous fit it will have
> been overwritten by the newer fit. Some of the other info, such as
> R-factor by k-weight seems to get overwritten too.
I just pushed a fix for this to github and posted new windows installer
candidates at
@millenia.cars.aps.anl.gov
Subject: [Ifeffit] What you see is "not" what you get: help
Hi folks,
I´ve been working on Xanes peaks fitting with Athena (last version) and I
found a strange behaviour. I get a "good" fit looking to the Graphics
Window of Athena and to the minimized parameters (R-f
work they included standards which had SPOIL values greater
than 6, so they would have rejected a standard with a value lower than 6))
2. Malinowski, E. R., Factor Analysis in Chemistry. Wiley: New York, 2002; p
432.
I might be wrong on this but when these programs use the formulas for
calculat
Bruce and Matt:
When Athena and Artemis are completely moved to BlackBerry and iPhone, there
will be a number of really nice options out there. For example, ringtones for a
really bad fit should be made very unpleasant, and even more so, when Delta E0
is out of bounds, or r-factor is greater
distances from such an analysis is to assert that the difference between
the path is a fixed value and thus refine the two paths with the same delta R
(and probably the same debye wller factor) this in my experience works in some
cases
Best regards
Fred Mosselmans
-Original Message-
From
e:
Bruce,
Perhaps you noticed the "Fit color" was red (large R-factor 0.074496,
poor fit, also seen in the attached figure in the last email) when you
loaded in the project file I sent you. When you hit Fit button again the
"Fit color" might turn to green indicating good fit
, and is not completely reversible. I see a factor of 1000
as a multiplicative factor in the Energy Text Control window when "keV" is
selected, but this appears to not be editable.
I also see that this only happens when using the Larch backend and not the
Ifeffit backend. And, I can als
f the Vogt–Mizaikoff F-test to determine the number of
principal factors responsible for a data matrix and comparison with other
popular methods. Journal of Chemometrics, 2004. 18(9): p. 387-392) is
stated that s is equal to r or c, wichever is smaller, in this case s=c,
the number of spectra as you said.
Y
be displayed correctly in the history window.
>> Now change the R window (say 1.5-3.5) and run the fit again. When you go
>> to the history window the R window information will be displayed
>> correctly for the most recent fit but, for the previous fit it will have
>> been
; this point the log will be displayed correctly in the history window.
> Now change the R window (say 1.5-3.5) and run the fit again. When you go
> to the history window the R window information will be displayed
> correctly for the most recent fit but, for the previous fit it will have
>
hello
Two phase can be mixed in ZnS. You need to check r-factor and reduced-chi
squrare with two model.
If you want to fit only first shell,
I suggest.
first use cubic zinc-blende model in FEFF, and check goodness of fit.
second, fix the bond length of 3 bonding length and change the bond
is purely made up, as far as I know. It's
like saying the fit is pretty close to the data
when the EXAFS R-factor is less than 0.02. That
0.02 is arbitrary, but works as a rule of thumb.
I myself don't always pay attention to the 2/3
that I have occasionally mentioned. I'm pretty
work, I got it to the point that the fit looks pretty (R-factor<0.02), but I
have several reservations about it:
1) Generally, the ss values are all higher than I would like. 0.007 even
seems high to me for a metal-O bond. Am I right about this? Would this indicate
that this may have b
Julian:
I agree with Anatoly. The amplitude of the EXAFS is quite large. I have seen
a similar effect in metal foils and NP samples when you forget to take the
log of the I0 and IT. This also forces the S02 factor to be artificially
high (like it is for your samples) when fitting in Artemis. Maybe
the Hanning window
I used a dk of 1, and for the K-B window i tried different dk's from 1-5.
The kmin and kmax were held constant at 2.5-11. I did notice the large
increase in ringing with the low dk values and the K-B window. The fit
quality, by R-factor, was substantially worse with
Hi Matt,
Thank you for your answer and for taking time to explain me basic things again
and again.
I have completely different question as well, and hopefully the last one for a
while: I just started using Artemis, and have a question regarding the
amplitude reduction factor: I use
I tried running a combinatorial LCF series just before writing this
email and I think these numbers are reported correctly. If you think
otherwise, you will need to show me an example.
Of course, the values for both R-factor and reduced chi-square are
rather peculiar in Athena's LC fitting, as
;s saying
that there is a 23% that, given the noise level in the data, the fit would
indicate that C was present when it was not. That is /not/ the same thing as
saying there is a 77% chance of C being present.
To see this, imagine very, very noisy data. Including C in the fit might very
well i
On 07/14/2015 10:18 AM, Neeb, Matthias wrote:
I have a standard exafs spectrum of copper K-shell and everything
looks as expected (Chi(E), Chi(k), Chi(R), Chi(q) …) when using
Demeter 0.9.21 .
However the phase spectrum of (Chi(q)) appears quite different to
literature (e.g. B.K. Teo
we think this is strange, because putting 8
imidazoles around a zinc seems kind of silly but it likes it. 5
imidazoles and 3 sulfurs and I have an R-factor of 0.2% every time.
If there is non standard multiple scattering that occurs in multiple
unrelated proteins from different organisms then w
should be included. I remember coming
>> across a website that had this information on it awhile ago but I can't
>> seem to find my way back. We would like to publish a qualitative XANES
>> paper and an EXAFS paper. Any suggestions on the type of information
>> (plots, t
tistics
Number of independent points : 0
Number of variables : 0
Chi-square : 0
Reduced chi-square : 0
R-factor : 0
Measurement uncertainty (k) : 0
Measurement uncertainty (R) : 0
Guess parameters
=*==*==*==*==*==*==*==*==*==*==*==*
Hi Carlo
Thank you for your answer. I have completely different question as well: I
just started using Artemis, and have a question regarding the amplitude
reduction factor: I use different So^2 for different elements, correct? If I
start fitting and have paths involving the same kind of atom but
list below, then, gives a result of 0.64, which indicates
such variation is quite likely to have taken place by chance.
You chose the worst case of your three, though; the pH 3 case. The pH 10 case
shows the most improvement in the R-factor with x = 0.007/0.012 = 0.58. The
probability of getting
home for war, and has many adventures on his way
home which might prevent him from ever getting back. Meanwhile, there
is a long line of people waiting to take his place at home.
> In the next sentence, what is the overall amplitude factor S_0^2? How is
> it defined?
S_0^2 accounts for the rela
R-space there is no local minima. For Cobalt and Nickel samples I typically
get one or a few fits that are obviously significantly better in R-factor (with
reasonable distances, sigma^2, etc) but for Zinc this is not the case.
I can get many good fits and Zinc likes to increase the coordination up
Good afternoon
I understand. In that case, would it be possible for you to perhaps guess
the greatest factor causing this problem? My apologies if I may be asking
for too much.
Yours sincerely
Deepak Varanasi
On Sun, Sep 13, 2020, 16:39 Deepak Varanasi wrote:
> Good afternoon
>
> T
large compared with the R from literature. But if I force sigma^2 to
be positive and e_2 to be below 10 ev, the R-factor will increase and the
fitting doesn't seem good.
As for the 2.59 Angstrom for equatorial U-O, it is even a little bit larger
than the bidentate U-O. I don't think it
ely change with k, but that would surely be dominated by the rapid decay
> in |chi(k)|, rather than a change in epsilon.
>
> I'm confused. We Fourier transform k-weighted data. Since Ifeffit uses the
> high-R amplitude to estimate uncertainty, it seems to me that what matters
> i
Something is horribly wrong with the data here.
I overplotted your reference Au foil against mine, and yours has distorted
XANES and too high EXAFS intensity compared to my data. Your amplitude factor
is 1.54 which also confirms that something was wrong in the experiment. Perhaps
- a
- 0.01) and if I try to do the same with the 4th parameter no fit at all
> takes place. The errors in the GDS-window are exactly 0.0 with no fit
> taking place (enot = 0, amp = 0 (guess amp = 1) delr = 0 and ss = 0.003)
> and the R-factor of the fit is way over the top (>10^20).
>
>
ep a close eye on the "Reduced Chi-square"
as you add more "guess" parameters. If it goes up, you may be
overreaching on your model even though the "R-factor" goes down!
HTH
Carlo
--
Carlo U. Segre -- Professor of Physics
Associate Dean for Special Projects
be a number of really nice options out there. For example,
> ringtones for a really bad fit should be made very unpleasant, and even more
> so, when Delta E0 is out of bounds, or r-factor is greater than 0.02..
>
> Anatoly
>
> -Original Message-
> From: ifeffit-
ersion "Artemis 0.9.26" I have two
> problems. (1) The fitting Range was reported to be a error that the Rmin
> should be larger than the Rkbg value. It makes that the fitting range cannot
> be smaller than 0.9 (the Rkbg value is 0.9). (2) When Fitting the
> Debye–Waller fa
, namely Li2Se. I try to include a scattering path from the
respective Li2Se crystal model in my fits, since a Se (absorber) - Li
(backscatterer) pair is present in the R-range of my fit in the Forward
Fourier Transform. My question here is if this makes sense since Li is
much smaller scatterer
rocedure in which an effective scattering factor
f_eff,j(r,theta_j) which depends on r takes the place of the usual PW
[plane wave] f_j(theta_j)."
In addition, was FEFF3 a multiple-scattering code? The comments in its
header and the 1991 JACS article on it mention only single-scattering.
It
Hi Scott,
That's a pretty amazing use case.
But I'm not sure I understand the issue exactly right. I would have
thought the volume (r**3) was the important physical parameter, and
that a 1000nm particle would dominate the spectra over 3nm particles.
Or is it that you are
e most improvement in the R-factor with x = 0.007/0.012 = 0.58. The
probability of getting that much improvement by chance drops to 0.30—less
likely, but still pretty close to a coin flip.
Even the fact that you got all three to show improvement doesn’t quite reach
the 95% confidence level, althoug
.
In looking at the structures of Al2O3 and Y2O3, I noticed a couple of
interesting issues. The first shell in the Al2O3 structure is
# Atom R
3 O 1.8519
3 O 1.9717
The Y2O3, however seems to have two diffente Y sites, and the first shells
are
Site 1
One possible scenario: If one site has 6 nearest neighbors and the other - 4,
and if you choose the site with 4 neighbors to construct FEFF to model your
EXAFS data; and if you set your degeneracy equal to 4 and make your amplitude
factor as S02*x of one site + S02*(1-x) of another site, then
cause they are what are typically found in actual analysis of real
data.
> Several months ago, I wrote to the mailing list regarding the difference
> of fitting in R- and k-space in Artemis and received several responses
> revealing that some comments made in the Koningsberger rev
.
As you can see, the fit contains four paths. They are all single scattering paths,
and the paths with the four largest ranks according to feff. All paths share the
same SO2 and deltaE. Each path has its own delR and ss. After some work, I got it
to the point that the fit looks pretty (R-factor
atom of Co, you can also calculate the volume fraction in a
cubic centimeter of material.
To do so, you need to firstly obtain the (short-ranged) lattice parameter (in
angstrom) of each phase from an EXAFS fitting with an R-factor less than 0.02.
Then the volume (in angstrom cube) of the unit ce
t me know.
> Thank you in an anticipation
> Best
> Pushkar
>
>
> Independent points : 16.125
> Number of variables : 4
> Chi-square : 7324.9401796
> Reduced chi-square : 604.118
>
> R-factor:
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