70
4 Solid and Liquid Skins
226.5 227.0 227.5 228.0 228.5 229.0
Intensity (a.u.)
BE (eV)
Exp
Fit
B
S 2
S 1
Mo(100) 3d 5/2
(a)
226.5 227.0 227.5 228.0 228.5 229.0
Intensity (a.u.)
BE (eV)
Exp
Fit
B
S2
S1
Mo(110) 3d 5/2
(b)
Fig. 4.8 Decomposition of the 3d 5/2 spectra of a Mo(100) and b (110) [13, 50] skins using B, S 2
and S 1 components with derivatives shown in Table 4.2
Table 4.2 Sublayer-resolved atomic CN(z), E ν (z), E ν (0), bulk shift ΔE ν (12), strain ε r , relative bond
energy δE z , relative cohesive energy δE coh , and relative energy density δE den , for the bcc-structured
W [48, 49, 51], Mo [13, 50] and Ta [6, 52]
i
z
W 4f 7/2 Mo
3d 5/2
Ta 4f 7/2 −ε z
(%)
δE z
−δE coh
δE den
m
1 [53]
1 [54]
1 [6,
52]
E ν (0)
–
0
28.889
224.868
19.368
E ν (12)
B
12
31.083
227.567
21.650
0
0
0
0
E ν (12)
–
2.194
2.699
2.282
σ
0.002
0.002
0.002
(100)
S 2
5.16
31.283
227.813
21.855
8.27
9.01
53.13
41.21
S 1
3.98
31.398
227.957
21.977
12.53
14.32
62.08
70.81
(110)
S 2
5.83
31.240
227.761
21.811
6.60
7.07
47.98
31.43
S 1
3.95
31.402
227.962
21.981
12.67
14.51
62.31
71.92
(111)
S 2
5.27
31.275
–
21.847
7.96
8.65
52.28
39.37
S 1
4.19
31.370
–
21.949
11.60
13.12
60.50
63.73
addition of defects or adatoms, rather than two in the fcc and bcc structures, because
of the smaller Be atomic cross-section and the high packing density. The lacking of
bulk information in the Be(1120) spectrum also indicates the penetration depth of
the 135 eV X-ray beam limiting only to the outermost three atomic layers – less than
1 nm thick.
Figure 4.10 shows the decomposition of the 3d 5/2 spectra for the Ru(0001) and
Ru(1010) [22, 65] skins with derived information featured in Table 4.4. Figure 4.11d–
f show the decomposed 4f spectra for the Re(0001) and Re(1231) skins. With respect
to the data source, these skins are decomposed into 3 and 4 components, respectively,
because of the Re(1231) kinks. There is a total of n = 8 components and 28 possible
E ν (0) values for average. The optimized z value of 2.836 for the Re(1231) outermost
4 Solid and Liquid Skins
226.5 227.0 227.5 228.0 228.5 229.0
Intensity (a.u.)
BE (eV)
Exp
Fit
B
S 2
S 1
Mo(100) 3d 5/2
(a)
226.5 227.0 227.5 228.0 228.5 229.0
Intensity (a.u.)
BE (eV)
Exp
Fit
B
S2
S1
Mo(110) 3d 5/2
(b)
Fig. 4.8 Decomposition of the 3d 5/2 spectra of a Mo(100) and b (110) [13, 50] skins using B, S 2
and S 1 components with derivatives shown in Table 4.2
Table 4.2 Sublayer-resolved atomic CN(z), E ν (z), E ν (0), bulk shift ΔE ν (12), strain ε r , relative bond
energy δE z , relative cohesive energy δE coh , and relative energy density δE den , for the bcc-structured
W [48, 49, 51], Mo [13, 50] and Ta [6, 52]
i
z
W 4f 7/2 Mo
3d 5/2
Ta 4f 7/2 −ε z
(%)
δE z
−δE coh
δE den
m
1 [53]
1 [54]
1 [6,
52]
E ν (0)
–
0
28.889
224.868
19.368
E ν (12)
B
12
31.083
227.567
21.650
0
0
0
0
E ν (12)
–
2.194
2.699
2.282
σ
0.002
0.002
0.002
(100)
S 2
5.16
31.283
227.813
21.855
8.27
9.01
53.13
41.21
S 1
3.98
31.398
227.957
21.977
12.53
14.32
62.08
70.81
(110)
S 2
5.83
31.240
227.761
21.811
6.60
7.07
47.98
31.43
S 1
3.95
31.402
227.962
21.981
12.67
14.51
62.31
71.92
(111)
S 2
5.27
31.275
–
21.847
7.96
8.65
52.28
39.37
S 1
4.19
31.370
–
21.949
11.60
13.12
60.50
63.73
addition of defects or adatoms, rather than two in the fcc and bcc structures, because
of the smaller Be atomic cross-section and the high packing density. The lacking of
bulk information in the Be(1120) spectrum also indicates the penetration depth of
the 135 eV X-ray beam limiting only to the outermost three atomic layers – less than
1 nm thick.
Figure 4.10 shows the decomposition of the 3d 5/2 spectra for the Ru(0001) and
Ru(1010) [22, 65] skins with derived information featured in Table 4.4. Figure 4.11d–
f show the decomposed 4f spectra for the Re(0001) and Re(1231) skins. With respect
to the data source, these skins are decomposed into 3 and 4 components, respectively,
because of the Re(1231) kinks. There is a total of n = 8 components and 28 possible
E ν (0) values for average. The optimized z value of 2.836 for the Re(1231) outermost