Empirical Mass Absorption Coefficients

Empirical Mass Absorption Coefficient File

Empirical MAC (Mass Absorption Coefficients) are stored in a file called EMPMAC.DAT in the XRAYDATA sub directory (usually "C:\Program Files\Probe for Windows"). If the user obtains any new empirical MAC data the file can be edited using any text editor such as NotePad or NoteBook. Be careful to avoid adding any <tab> characters when editing the file (use space or comma delimited values only). The values can then be accessed using from the Analytical | Empirical MACs menu for runs that contains a matching emitter and absorber binary. Any changes to the default MAC values will be stored in your .MDB database file. Note that the elements may be in any order although they have been sorted to facilitate editing.

The format of the EMPMAC.DAT file is shown below :

"b" "ka" "b" 3471 "Pouchou (1992)"
"b" "ka" "c" 6750 "Pouchou (1992)"
"b" "ka" "n" 11000 "Pouchou (1992)"
"b" "ka" "o" 16500 "Pouchou (1992)"
"b" "ka" "al" 64000 "Pouchou (1992)"
"b" "ka" "si" 80000 "Pouchou (1992)"
"b" "ka" "ti" 15000 "Pouchou (1992)"
"b" "ka" "v" 18000 "Pouchou (1992)"
"b" "ka" "cr" 20700 "Pouchou (1992)"
"b" "ka" "fe" 27800 "Pouchou (1992)"
"b" "ka" "co" 32000 "Pouchou (1992)"
"b" "ka" "ni" 37000 "Pouchou (1992)"
"b" "ka" "zr" 4400 "Pouchou (1992)"
"b" "ka" "nb" 4500 "Pouchou (1992)"
"b" "ka" "mo" 4600 "Pouchou (1992)"
"b" "ka" "la" 2500 "Pouchou (1992)"
"b" "ka" "ta" 23000 "Pouchou (1992)"
"b" "ka" "w" 21000 "Pouchou (1992)"
"b" "ka" "u" 7400 "Pouchou (1992)"
"c" "ka" "b" 39000 "Pouchou (1992)"
"c" "ka" "c" 2170 "Pouchou (1992)"
"c" "ka" "si" 35000 "Pouchou (1992)"
"c" "ka" "ti" 8097 "Pouchou (1992)"
"c" "ka" "v " 8850 "Pouchou (1992)"
"c" "ka" "cr" 10700 "Pouchou (1992)"
"c" "ka" "fe" 13150 "Pouchou (1992)"
"c" "ka" "zr" 25000 "Pouchou (1992)"
"c" "ka" "nb" 24000 "Pouchou (1992)"
"c" "ka" "mo" 20500 "Pouchou (1992)"
"c" "ka" "hf" 18000 "Pouchou (1992)"
"c" "ka" "ta" 17000 "Pouchou (1992)"
"c" "ka" "w" 18000 "Pouchou (1992)"
"n" "ka" "b" 15800 "Pouchou (1992)"
"n" "ka" "n" 1640 "Pouchou (1992)"
"n" "ka" "al" 13800 "Pouchou (1992)"
"n" "ka" "si" 17000 "Pouchou (1992)"
"n" "ka" "ti" 4270 "Pouchou (1992)"
"n" "ka" "v " 4950 "Pouchou (1992)"
"n" "ka" "cr" 5650 "Pouchou (1992)"
"n" "ka" "fe" 7190 "Pouchou (1992)"
"n" "ka" "zr" 24000 "Pouchou (1992)"
"n" "ka" "nb" 25000 "Pouchou (1992)"
"n" "ka" "mo" 25800 "Pouchou (1992)"
"n" "ka" "hf" 14000 "Pouchou (1992)"
"n" "ka" "ta" 15500 "Pouchou (1992)"
"o" "ka" "li" 1600 "Bastin (1992)"
"o" "ka" "b" 8550 "Bastin (1992)"
"o" "ka" "b" 1200 "Bastin (1992)"
"o" "ka" "f" 1850 "Love et al. (1974)"
"o" "ka" "ne" 2750 "Love et al. (1974)"
"o" "ka" "na" 3630 "Love et al. (1974)"
"o" "ka" "mg" 5170 "Bastin (1992)"
"o" "ka" "al" 6720 "Bastin (1992)"
"o" "ka" "si" 8790 "Bastin (1992)"
"o" "ka" "p" 9820 "Love et al. (1974)"
"o" "ka" "s" 12400 "Love et al. (1974)"
"o" "ka" "cl" 14300 "Love et al. (1974)"
"o" "ka" "ar" 16100 "Love et al. (1974)"
"o" "ka" "k" 20500 "Love et al. (1974)"
"o" "ka" "ca" 24600 "Love et al. (1974)"
"o" "ka" "sc" 26800 "Love et al. (1974)"
"o" "ka" "ti" 19900 "Bastin (1992)"
"o" "ka" "cr" 2900 "Bastin (1992)"
"o" "ka" "mn" 3470 "Bastin (1992)"
"o" "ka" "fe" 4000 "Bastin (1992)"
"o" "ka" "co" 4500 "Bastin (1992)"
"o" "ka" "ni" 5120 "Bastin (1992)"
"o" "ka" "cu" 5920 "Bastin (1992)"
"o" "ka" "zn" 6350 "Bastin (1992)"
"o" "ka" "ga" 7090 "Bastin (1992)"
"o" "ka" "y" 15100 "Bastin (1992)"
"o" "ka" "zr" 16200 "Bastin (1992)"
"o" "ka" "nb" 17100 "Bastin (1992)"
"o" "ka" "mo" 18000 "Bastin (1992)"
"o" "ka" "ru" 19700 "Bastin (1992)"
"o" "ka" "sn" 15050 "Bastin (1992)"
"o" "ka" "ba" 4560 "Bastin (1992)"
"o" "ka" "la" 3600 "Bastin (1992)"
"o" "ka" "ta" 10600 "Bastin (1992)"
"o" "ka" "w " 11300 "Bastin (1992)"
"o" "ka" "pb" 11000 "Bastin (1992)"
"o" "ka" "bi" 12100 "Bastin (1992)"
"f" "ka" "xe" 27300 "Henke et al. (1982)"
"na" "ka" "zn" 10500 "Henke et al. (1982)"
"na" "ka" "pm" 7920 "Henke et al. (1982)"
"mg" "ka" "tb" 8240 "Henke et al. (1982)"
"al" "ka" "tm" 4730 "Henke et al. (1982)"
"cr" "la" "te" 39500 "Henke et al. (1982)"
"co" "la" "co" 1920 "Henke et al. (1982)"
"ge" "ka" "ta" 265 "Henke et al. (1982)"
"ge" "la" "gd" 8500 "Henke et al. (1982)"
"mo" "la" "hg" 951 "Henke et al. (1982)"

The first column ("b" in the example equals Boron) is the atomic symbol of the emitting element. The second column ("ka" in the example equals Ka) is the x-ray line of the emitting element. The third column is the atomic symbol of the absorber element. The element and x-ray symbols must be enclosed in double quotes. The fourth column is the actual mass absorption coefficient (MAC) that has been experimentally measured. The last parameter is a comment string that may contain a comment, usually the experimenter or attribution. The comment string must be in double quotes.

The first and third columns (emitting atomic number and absorber atomic number) must be integer values from 1 to 94. The second column (x-ray line type) must be an integer value from 1 to 3. The fourth column (MAC value) must be a real number greater than zero.

 

Use of Empirical MACs

The following is a small compilation of mass absorption coefficients (MACs) from a number of investigators. Some of these MACs may be selected for use in the quantitative calculations in Probe for Windows, from the Analytical | Empirical MACs menu item. Up to MaxEmp% empirical mass absorption coefficients may be defined for each run. These MACs will be saved to the .MDB file for subsequent re-processing and can be added to, changed or deleted again.

 

Empirical Mass Absorption Coefficients (MACs)

Emitter Absorber Henke Ebisu Ruste Henke et al. Bastin Heijligers Heinrich Frazer Pouchou Pichoir
B ka B 3353   3350 3500     3471
B ka C 6456   6350 6500     6750
B ka N 10570   11200 11200     11000
B ka O             16500
B ka Al 65170   64000 64000     64000
B ka Si 74180   84000 84000     80000
B ka Ti 15280   15300 14700     15000
B ka V 16710   16700 17700     18000
B ka Cr 20670   20700 20200     20700
B ka Fe 25780   27600 27300     27800
B ka Co 28340   30900 33400     32000
B ka Ni 33090   35700 42000     37000
B ka Zr 384101   8270 4000     4400
B ka Nb 4417   6560 4600 3822   4500
B ka Mo 4717   5610 4550 4208   4600
B ka La 3826   3730 2500 11654   2500
B ka Ta 20820   20800 22500     23000
B ka W 19660   19700 21400     21000
B ka U 2247   9020 8200     7400
                 
C ka B 37020 37020 37000 41000     39000
C ka C 2373 2373 2350 2373 2147   2170
C ka Si 36980 36980 36800 37000     35000
C ka Ti 8094 8094 8090 9400 8290   8097
C ka V 8840 9236 8840 10100     8850
C ka Cr 10590 10482 10600 10950     10700
C ka Fe 13300 13300 13900 13500 14103   13150
C ka Zr 31130 31130 21600 24000 31304   25000
C ka Nb 339901 24203 19400 23200 29760   24000
C ka Mo 324201 15500 16400 19200     20500
C ka Hf             18000
C ka Ta 18390 20000 18400 16000     17000
C ka W 18750 21580 18800 17000     18000
                 
N ka B             15800
N ka N             1640
N ka Al             13800
N ka Si             17000
N ka Ti             4270
N ka V             4950
N ka Cr             5650
N ka Fe             7190
N ka Zr             24000
N ka Nb             25000
N ka Mo 23220   20200   26458   25800
N ka Hf             14000
N ka Ta             15500
                 
O ka Li 1602   1600 1600      
O ka B 7416   7420 8550      
O ka O 1200   1200 1200      
O ka Mg 5174   5170 5170      
O ka Al 6715   6720 6720      
O ka Si 8790   8790 8790      
O ka Ti 22140   22100 19900      
O ka Cr 3143   3140 2900      
O ka Mn 3468   3470 3470      
O ka Fe 4001   4000 4000      
O ka Co 4407   4410 4500      
O ka Ni 5245   5120 5120      
O ka Cu 5920   5920 5920      
O ka Zn 6548   6550 6350      
O ka Ga 7086   7090 7090      
O ka Y 15140   15100 15100      
O ka Zr 16140   14800 16200      
O ka Nb 17850   15300 17100      
O ka Mo 18660   16700 18000      
O ka Ru 19680   19700 19700      
O ka Sn 23090   23100 15050      
O ka Ba 4560   4560 4560      
O ka La 4690   4690 3600      
O ka Ta 10560   10600 10600      
O ka W 10990   11000 11300      
O ka Pb 12470   12500 11000      
O ka Bi 12690   12700 12100      
                 
Al ka Al     403   397 404 393
Al ka Cu     4550   4764 5410 4588
                 
Si Ka Si     350   347 332 356
Si ka Ta     3760   1698   1500
                 
S ka Au         3380 3203 2200
S ka Hg         1499 932 850
                 
Sc la Sc             4750
Ti la Ti             4550
V la V             4370
Cr la Cr             3850
Mn la Mn             3340
Fe la Fe             3350
Co la Co             3260
Ni la Ni             3560
Cu la Al     1450   1421 1494 1464
Cu la Ni     11700   11776 12106 11879
Cu la Cu             1755
Zn la Zn     1520   1485 1581 1500
Ge la Ge     1260   1262 1278 1240
As la Ga             7000
Nb la Nb     726   718 726 779
Mo la Au     3680   3437   2200
W la W         1215 1458 1258
Au ma Au         1061 1101 1103
                 

1 extrapolated across absorption edge

K. F. J. Heinrich, "Mass Absorption Coefficients for Electron Probe Microanalysis" in Proc. 11th ICXOM 67: 1, 1982.
B. L. Henke, P. Lee, T. J. Tanaka, R. L. Shimabukuro and B. K. Fijikawa, Atomic Data Nucl. Data Tables 27, 1 (1982)
B. L. Henke and E. S. Ebisu, Adv. X-Ray Anal. 17, 150 (1974)
J. L. Pouchou and F. M. A. Pichoir, "Determination of Mass Absorption Coefficients for Soft X-Rays by use of the Electron Microprobe" Microbeam Analysis, Ed. D. E. Newbury, San Francisco Press, 1988, p. 319-324.
J. Ruste, J. Microsc. Spectrosc. Electron. 4, 123 (1979)

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