APPENDIX A
HOLZ PATTERN CALCULATION
Central to the calculations described in this
appendix is the assumption that the microscope
accelerating voltage can be arbitrarily defined. This
will in turn define a relative crystal standard for the
material that will be characterized. The standard
operating voltage of the microscope is defined to be
100.00 KeV, for which the wavelength will be .037
Angstroms. For B=<(ll4>and 9,3,1 diffracting planes, the
resultant lattice parameter that exactly satisfies the
equation in Section 4.1.3, is 3.5712 Angstroms. For the
standard values just given, the four 9,3,1 HOLZ lines will
intersect at a point in the center of the transmitted
disc. The ratio of A to B (see Figure A) is referenced at
this point to the values of A1 and B1 given in the
attached program listing. A larger or smaller lattice
parameter will cause this ratio to vary. The ratio is
listed as R1 in the table following the program.
To account for noncubic effects, values of A3 and B3
are also calculated in the program. They are ratioed in
the program and appear in the Table as the ratio R2. The
values TI, T2, etc. which appear in the program and in
Figure A are delta theta-Bragg values, where delta
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