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preface to fifteenth edition

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SPECTROSCOPY 7.7<br />

TABLE 7.2<br />

Wavelengths of Absorption Edges in Angstroms (Continued)<br />

A<strong>to</strong>mic<br />

No. Element K L I L II L III<br />

74 W 0.17837 1.025 1.074 1.215<br />

75 Re 0.1731 0.9901 1.036 1.177<br />

76 Os 0.1678 0.9557 1.001 1.140<br />

77 Ir 0.1629 0.9243 0.9670 1.106<br />

78 Pt 0.1582 0.8914 0.9348 1.072<br />

79 Au 0.1534 0.8638 0.9028 1.040<br />

80 Hg 0.1492 0.8353 0.8779 1.009<br />

81 Tl 0.1447 0.8079 0.8436 0.9793<br />

82 Pb 0.1408 0.7815 0.8155 0.9503<br />

83 Bi 0.1371 0.7565 0.7891 0.9234<br />

84 Po 0.1332 0.7322 0.7638 0.8970<br />

85 At 0.1295 0.7092 0.7387 0.8720<br />

86 Rn 0.1260 0.6868 0.7153 0.8479<br />

87 Fr 0.1225 0.6654 0.6929 0.8248<br />

88 Ra 0.1192 0.6446 0.6711 0.8027<br />

89 Ac 0.1161 0.6248 0.6500 0.7813<br />

90 Th 0.1129 0.6061 0.6301 0.7606<br />

91 Pa 0.1101 0.5875 0.6106 0.7411<br />

92 U 0.1068 0.5697 0.5919 0.7233<br />

93 Np 0.1045 0.5531 0.5742 0.7042<br />

94 Pu 0.1018 0.5366 0.5571 0.6867<br />

95 Am 0.0992 0.5208 0.5404 0.6700<br />

96 Cm 0.0967 0.5060 0.5246 0.6532<br />

97 Bk 0.0943 0.4913 0.5093 0.6375<br />

98 Cf 0.0920 0.4771 0.4945 0.6223<br />

99 Es 0.0897 0.4636 0.4801 0.6076<br />

100 Fm 0.0875 0.4506 0.4665 0.5935<br />

on the K and L wavelength values as published by Y. Cauchois and H. Hulubei (Tables de Constantes<br />

et Données Numériques, I. Longueurs d’Onde des Émissions X et des Discontinuités d’Absorption<br />

X, Hermann, Paris, 1947) and by the International Union of Crystallography (International Tables<br />

for X-Ray Crystallography, Kynoch Press, Birmingham, England, 1962). Wavelength accuracy is<br />

only <strong>to</strong> about 1 in 25 000 except for the lines employed in X-ray diffraction work.<br />

Use of energy-proportional detec<strong>to</strong>rs for X-rays creates a need for energy values of K and L<br />

absorption edges (Table 7.3) and emission series (Table 7.4). These values were obtained by a<br />

conversion <strong>to</strong> keV of tabulated experimental wavelength values and smoothed by a fit <strong>to</strong> Moseley’s<br />

law. Although values are listed <strong>to</strong> 1 eV, chemical form may shift absorption edges and emission<br />

lines as much as 10 <strong>to</strong> 20 eV. S. Fine and C. F. Hendee [Nucelonics, 13(3):36 (1955)] also give<br />

values for K 2 , L 1 , and L 2 lines.<br />

The relative intensities of X-ray emission lines from targets varies for different elements. However,<br />

one can assume a ratio of K 1 /K 2 2 for the commonly used targets. The ratio of K 2 /K 1<br />

from these targets varies from 6 <strong>to</strong> 3.5. The intensities of K 2 radiations amount <strong>to</strong> about 1 percent

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