Appl. Phys. A55, 258-260 (1992)
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© Springer-Verlag 1992
A Note on X-Ray Raman Scattering from Boron
D.K. Papademitriou and A.D. Zdetsis
1 Department of Physics, University of Ioannina, P.O. Box 1186, 45110 Ioannina, Greece
2 University of Patra, Department of Physics, Patra, Greece
Received in revised form 16 March 1992/Accepted 27 March 1992
Abstract. A systematic study of the spectra of inelastically
scattered X-ray radiation from Boron irradiated by Cu K~
radiation is presented. The results for the angular dependence
of the intensity of Raman bands at lower scattering angles are
in good agreement with the theoretical predictions. However,
a clear discrepancy appears at higher scattering angles which
is very different from the one which appears for other light
elements (Lithium, Beryllium, Graphite).
PACS: 78.70.Ck
a discrepancy in the angular dependence of the intensity of
Raman bands for high scattering angles. This fact lead us to
a more systematic and detailed study of the integrated inten-
sities of the Raman bands for a wide range of ~o. Therefore,
in the present work using the Cu K;~ X-ray radiation of a
copper tube and Boron as scatterer we studied the angular
dependence of the intensity of X-ray Raman scattering at
scattering angles qo from 35 ° to 110.0 ° in steps of 5 ° using a
single crystal spectrometer with a resolution of about 1050.
Our purpose is to resolve this important question mostly
concerning the high qo values.
In our previous work [1] a study was carried out on the
spectra of inelastically scattered Cu K,~l,a 2 X-ray radiation
by polycrystalline Be. In that work we studied the angular
dependence of the intensity of X-ray Raman scattering at dif-
ferent scattering angles. We confirmed that the dependence
of the intensity upon the scattering angles qo at lower scat-
tering angles is well predicted by the theoretical relationship
[1],
Itheor (3( (1 + cos 2 ~) sin 2 ~o/2.
i
This formula for the intensity had been theoretically deter-
mined by Mizuno and Ohmura [2]. The main features of the
experimentally determined curve
I=aY,
where
Y = (1 + c0 s2 ~) sin 2 ~/2 and a = constant
were: a) the linear dependence of Taman intensities as a
function of Y at lower scattering angles in agreement with
the theoretical predictions and b) a small deviation from
linearity for scattering angles qo > 65.0 °.
In a recent work [3] on the observation of the anomalous
peaks at the long wavelength side of the Raman bands, the
set of spectra for scattering angles ~ in the range from 45 °
to 105.0 ° in steps of 10°, were determined. They showed
Experimental
The experimental arrangement and procedure have been pre-
viously described in detail [1]. The X-ray tube was operated
at 55kV and 190mA and the used scatterer was Boron pow-
der with a purity of 99.9%. AGe single crystal (220) ori-
entation and 2d = 4.00A was used as an energy analyser
because of higher intensity. The spectra were obtained using
a scintillation counter by step-scanning. An automatic step-
scanner of 0.01 ° was used and the time duration of each
step was set to 400 s. The spectra were scanned 5 times in
order to improve the statistical error which is estimated to
be 1.5%.
Results and Discussion
The obtained X-ray spectra were taken at eleven different
scattering angles qo from 35.0 ° to 110.0 ° as mentioned above.
In Fig. 1 four of the observed X-ray spectra at scattering an-
gles ~o of 45.0 °, 65.0 °, 85.0 °, and 105.0 ° are shown. By
subtracting the Compton bands C from the experimentally
obtained curves we succeeded to distinguish the X-ray Ra-
man bands. This separation was successful for scattering an-
gles qo higher than the critical scattering angle [4] so that the
shape of a Compton band is a parabola. At the lower scatter-
ing angles ~p, the separation of X-ray Raman scattering bands