Chemistry Reference
In-Depth Information
(a)
Δ
E
ex.
E
E
0
gd
Source & absorber
V
zz
>0
(b)
±3/2
Δ
E
q
3/2
±1/2
1/2
Quadrupole splitting
+3/2
(c)
+1/2
3/2
-1/2
-3/2
-1/2
1/2
+1/2
Nuclear Zeeman splitting
Fig. 1.6 Shift and splitting of nuclear levels of
57
Fe nucleus by the hyperfine interactions and
expected Mössbauer spectra. a Center shift of the observed absorption line. In this case the
observed shift is the sum of isomer shift and second order Doppler shift. b Electric quadrupole
splitting DEq and c magnetic hyperfine splitting that is a nuclear Zeeman splitting. H
hf
is the
magnitude of the hyperfine magnetic field at nucleus
using a proper coordinate system and can be completely specified by three com-
ponents o
2
V
=
oz
2
those are generally denoted as V
xx
,V
yy
and V
zz
. These three components must obey the following Laplace equation,
2
V
=
ox
2
, o
2
V
=
oy
2
and o
V
xx
þ
V
yy
þ
V
zz
¼
0
:
