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M. Chudzicki, W.S.M. Werner, A. Shard, Y. Wang, D. Castner, C.J. Powell:
"Correction to "Evaluating the Internal Structure of Core-Shell Nanoparticles Using X-ray Photoelectron Intensities and Simulated Spectra"";
Journal of Physical Chemistry C, 120 (2016), 2484.

We wish to correct some statements on pages 17689 and
17690 that pertain to information and results presented
in our Figures 1 and 2.
(1) The information in Figure 1 and the results in Figure 2
that are shown for Pd/Al2O3 nanoparticles (consisting of an
Al2O3 core and a Pd shell) were actually obtained for Pd-shell/
Al-core nanoparticles.
(2) The results in Figure 2 were obtained from SESSA
simulations in which inelastic mean free paths (IMFPs) from
the TPP-2M predictive formula of Tanuma et al.1 were
employed, not attenuation lengths (ALs) as stated in the paper.
(3) The parameter L1,a in the Shard T(NP) formula is
defined by Shard2 as an attenuation length for photoelectrons
from the shell in the shell material. Page 17689 and Figure 1
show L1,a values for Be/Au and Pd/Al2O3 nanoparticles that are
actually IMFPs from the TPP-2M formula, not ALs.
Furthermore, the L1,a (IMFP) value for Pd photoelectrons in
Pd, given as 1.20 nm, should actually be 1.55 nm.
(4) Evaluations of shell thicknesses, TNP, from the T(NP)
formula were made with IMFPs from the TPP-2M formula, not
ALs. The deviations from linearity in the right-most panels of
Figure 2 (where TNP is plotted against TSESSA, the shell
thicknesses used in the SESSA simulations, for Pd-shell/Al-core
nanoparticles) can be interpreted as being due to the effects of
elastic scattering, as stated in the manuscript. These deviations
are due to the choice of using IMFPs rather than ALs in the
T(NP) formula, as will be shown in a future paper.
We would also like to provide the following additional
information that was omitted from our paper. The SESSA
simulations for the results in Figure 2 of our paper were
performed for Be 1s, Au 4f7/2, Pd 3d5/2, and Al 2p3/2
photoelectrons excited by Al Kα X-rays. The X-rays were
incident at an angle of 60° with respect to the surface normal
and photoelectrons emitted normally from the nanoparticle
surface were detected. Values of the parameter B = L1,a/L2,a in
the Shard T(NP) formula were 0.856 and 0.984 for the Pd/Al
and Be/Au systems, respectively. Similarly, values of the
parameter C = L2,a/L2,b in the Shard T(NP) formula were
0.582 and 2.030 for the Pd/Al and Be/Au systems, respectively.
Evaluations of these two parameters were made with IMFPs
from the TPP-2M formula, not ALs.