makes the convergent beam method uniquely suitable for

other purposes, however. These are reviewed in the

following chapter.

 Convergent beam microdiffraction is also a spatially

 localized diffraction method. Again, only hundreds of

 square Angstroms are analyzed. The diffraction pattern

 consists of discs rather than spots. These discs are

 quite small in comparison to normal CBED discs and may be

 dimensionally comparable to the spots seen in selected

 area and Riecke patterns. If subtle diffraction effects

 are present, they will not be masked if this diffraction

 method is used.

 In addition to electron diffraction, the electron

microscopes were used to produce bright field, dark field,

and lattice images. The 400 FEG instrument was also used,

in conjunction with a KEVEX energy dispersive x-ray

detector and a DEC 1103 minicomputer, as an analytical

x-ray system for x-ray analysis of the RSR alloys. The

data reduction scheme for quantification was developed by

Zaluzec (1978). Details of these analyses are discussed

in the following chapter.

 To test the accuracy and applicability of the

convergent beam diffraction method for the measurement of

local lattice parameters, the lattice parameters of the

RSR alloys were measured using x-ray diffraction. The