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BELL SYSTEAf TECHNICAL JOURNAL 



is not 0°, such as the NT cut, these two axes will not be the same as those 

 used in checking the finished plate and different settings of the jig-holder 

 and ionization chamber will have to be calculated. The procedure is 

 similar to that for the determination of the g angles for the finished plate 

 except that the components of the unit vector of the atomic plane used are 

 multiplied by the matrix which expresses the transformation after two 

 rotations (.4i and .42) (equation 3.7) instead of the matrix for three rota- 

 tions. 



XJ 



Fig. 3.30 — Orientation of NT plate and slab with respect to Z section (-1-A'' toward 

 reader for right-handed quartz) 



For example, in the case of the NT cut, Ai = 99°25' and Ao = 49°20' 

 so that the .4i.42 matrix (equation 3.7) becomes 



/-.1636 .9865 \ 



;." = [ -.6429 -.1066 -.7595] 



\-.7483 -.1241 .6517/ 



which, multiplied by the components of the unit normal to the atomic plane 



/.5914\ 

 (2T • 3) in terms of the X, Y, Z axes j 1 gives the components of the unit 



\.8064/ 



