Powder photographs of two specimens A and B

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The discussion focuses on analyzing powder photographs of two cubic specimens, A and B, with A being pure and B containing impurities that create additional lines. The unit cell dimension of specimen A is determined to be 6.576 angstroms, prompting inquiries about the probable lattice types for both specimens, identification of impurity lines in B, and calculations for the wavelength of radiation and dimensions of lattice B. Participants seek guidance on deriving the interplanar spacing (d) from the provided equations, as well as methods to extract the indices (h, k, l) from the data. The conversation emphasizes the need for clarity in the analysis of the experimental results and the relationships between intensity and d.
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powder photographs of two specimens A and B, are taken with a camera of radius 9cm.the arc ( difference between coresponding lines on the film )are shown in the pure below. both of which are known to belong to the cubic system sepcimen A is pure while B contains some impurities which gives rise to three lines.the unit cell dimension of Ais 6.576 angstroms .
1- suggest the probable lattice type of A and B .
2- IDENTIFY TH THREE IMPURITY LINES IN SAMPLE B.
3- FIND THE WAVELENGTH OF THE RADIATION USED AND THE DIMENSION OF THE LATTICE B.
4- SHOW THAT YOUR SOLUATION GIVES SATISFACTORY AGREEMENT FOR ALL THE LINES ASSOCIATED WITH THE PURE SAMPLE AND GIVE THEIR INDICES.

LA cm : 25.28-24.60-24.02-23.51-23.04-22.20-21.81-21.45
LB cm : 23.94-22.09-20.80-20.62-19.33-18.16-17.06-15.99
LA cm : 21.10-20.76-20.43-20.11-19.48-19.81-21.10-20.76-20.43
LB cm : 14.95-13.93-13.50-12.94-11.88-11.20-14.95-13.93-13.50


RULES :
L/2R = (PI/2) - angle ( theta)........(1)

n ( wavelength) = 2dsin( theta ) .......(2)

d=a/ { (h^2)+(k^2)+(l^2) }^1/2.......(3)



ans:
we find ( theta) from (1) for every L , then we find d ..from d we find ( h.k.l) ..then we idenify the type of lattice ..


but how can i get d ? how can i drow the relations? how can i find exact value of ( h.k.l) from the drowing ?what is the relation between intensity and d ( rule ) ?
how can i analysis the experament? pleez anyone could help.. help me...
 
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pleez could anyone help?
 
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