HI Mike, it is dilute Pd in Au nanoparticles deposited on SiO2 with about
5% metal weight loading.
In my view, the lack of curvature in transmission (the original problem in
my post) is a simple consequence of two opposite trends, 1) the curving up
of the transmission signal by the same reason (yet
A question because I'm not really super clear on how harmonics work: (I'll get to the question in a moment...) I note that I0 starts to go non-linear around 12200-12400 eV and stays that way. So an increase (proportional?) in the amount of signal in It might be happening at around the same point.Co
Hi Anatoly,
I think Robert or Matthew made this point, but if set up for Pd, the mirror
angle may have been chosen to reject ~70 keV, but possibly not 36 keV --
the harmonic at the Au edge. Do you know what the mirror angle was?
The Ar-filled I0 would be very efficient at absorbing 12 keV, and o
Thank you, Matt. Ion chambers were filled with 90% Ar, and Pt coating was used, because we were measuring Pd K edge for the project, but we decided to look at the Au edge for testing purposes. AnatolyOn Jun 15, 2023, at 10:45 AM, Matt Newville wrote:I'm not sure why the intensity would go up unle
I'm not sure why the intensity would go up unless the ion chamber was
poorly set up. But, as others have pointed out, the mirror reflectivity
for a Pt mirror should not change significantly over this energy range -
the energy range is not that close to the Pt L3 or L2 edges.Depending
on where
renkel
To: XAFS Analysis using Ifeffit
Subject: Re: [Ifeffit] Brain teaser
Message-ID: <866eaccf-dad2-4486-aae0-ac3f6b280...@stonybrook.edu>
Content-Type: text/plain; charset=utf-8
Amazing idea. I thunk you were the only one who succeeded to use third harmonic
of Si for taking EXAFS at high a
Amazing idea. I thunk you were the only one who succeeded to use third harmonic
of Si for taking EXAFS at high atomic number elements. But that does not
explain the peaks and dips.
Anatoly
> On Jun 15, 2023, at 12:22 AM, matthew marcus wrote:
>
> Suppose the mono is being used at the 333 re
Suppose the mono is being used at the 333 reflection (for Si),
intentionally working at the 3rd harmonic. In that case, if the
fundamental isn't filtered out, you could get just what we see, with the
sample doing the filtering before the beam gets to the transmission chamber.
mam
On 6
Thank you, Matthew and Robert, but I think the explanation is more simplle. The
fact that there are peaks in I0 and dips in transmission is a clue that
explains why transmission is almost linear while I0 curves up.
Anatoly
> On Jun 14, 2023, at 11:34 PM, matthew marcus wrote:
>
> One thing
One thing that's pretty odd is that the glitches are peaks in I0, and
dips in It. It would be much easier to explain if It was the one that
increased steeply and I0 was more linear, but the presence of the edge
in It shows that you didn't switch them. Red = It. What's that sudden
drop at the
Hi Anatoly,
reflectivity of Pt over that energy range does not vary that much:
[image: image.png]
I guessed what angle you were set for, assuming Pd K-edge...
So something wrong with I0?
-R.
On Wed, Jun 14, 2023 at 5:28 PM Anatoly Frenkel <
anatoly.fren...@stonybrook.edu> wrote:
> Hello, all
Hello, all. It is a low- to medium- level brain teaser.
Pt-coated collimating mirror was in place for Pd K-edge measurement, but Au
L3-edge of Pd-Au alloy was measured (for testing purposes). I0 and It
detectors were both Ar filled ionization chambers. Because of the energy
dependence of reflectiv
12 matches
Mail list logo