Fault vector

FIGURE 2 Stacking sequence and associated stacking fault displacement vectors for three types of basal plane stacking fault in GaN. The double lines indicate the fault plane. The stacking fault vectors are shown for each fault. 

These stacking faults are often described by a fault vector Rp normal to the plane of the fault obtained by adding a lattice vector to R ... 

A partial dislocation (called a stair rod dislocation) is formed at the intersection of two stacking faults on different planes with different fault vectors R and R2 and its Burgers vector is bp = Ri—R2. An extended summary of the contrast from partial dislocations in fee metals has been given by Edington (1975). 

Figure 8.S. Projection onto a plane normal to 83 = [ 110] of the Si04 tetrahedra, showing the structure of a Brazil twin boundary parallel to r(IlOl) in which the right-handed quartz (lower-right) is displaced with respect to the left-handed quartz (upper-left) by a fault vector R= j[110].

Figure 8.12(a) is a two-dimensional representation showing the origin of a fault vector R associated with the presence of a slab of twin one unit cell thick. In the albite twin law, the two parts of the twin are related by a rotation of 180° about b. From Figure 8.12(b), we see that Rj is defined as... 

Figure 8.12. (a) Diagram showing the origin of a fault vector Rj due to a slab of twin one unit cell thick, (b) Diagram of the fault vector Rj for the unit cell axes of low albite. (From Fitz Gerald 1980.)... 

Table 8.5. Values of a = 2irg-R for the possible fault vectors of APBs in anorthite for b-, c-, and d-reflections...

Figure 9.31. Schematic diagram showing the dissociation of a dislocation into four partial dislocations (1-4) bounding three stacking faults with fault vectors R Rj, and R3.

It is clear that all fault vectors must be of the form R = [Ouw], and the proposed model (whose details need not concern us here) indicated that... 

Fault vector Fault plane Fault energy ( m Method... 

The ribbon width is variable and involves both glide and dimh, so that it may he nonequilibrium. The 1/4(111) fault vector causes initially empty sites in the perfect structure to he filled hy tetrahedral and dodecahedral cations, so that the SFE should be high. Equation (22) could not he detected in dislocations introduced into silicate... 

Fig. 3.69 Representative weak-beam dark-field (WBDF) images where dislocations Burgers vectors (b) and fault vector (Rp) of fault F were determined (transmission electron microscopy) [55], With kind permission of John Wiley and Sons...

The growth faults may correspond to marcasite lamellae in the pyrite [395,396]. Indeed HRTEM and electron diffraction revealed them as single (101) layers of marcasite inserted between (002) layers of pyrite [397]. Dislocation loops formed during the growth of pyrite also have the a[0, 0.27, 0.5] fault vector [101]. This translation was predicted as the most probable in a coincidence-site-lattice study [398]. 

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