The reflexion of X-rays from the ‘anti-phase nuclei’ of AuCu 3 . II
1966; Royal Society; Volume: 290; Issue: 1423 Linguagem: Inglês
10.1098/rspa.1966.0066
ISSN2053-9169
AutoresArthur James Cochran Wilson, L. Zsoldos,
Tópico(s)Theoretical and Computational Physics
ResumoA simplified method of calculating the diffraction patterns of crystals showing mistake broadening is outlined, and used to correct three results published by Wilson in 1943. Wilson’s model 3 (mistakes on {110} planes) is extended in the light of probable differences of the energy of interfaces between domains of different types. The apparent particle sizes obtained, when differences in interfacial energy are ignored, are: formistakes on { 100 } planes 3 N 1 2 / 2 ( h + k + l ) δ ; formistakes on { 110 } planes 3 ( 2 N ) 1 2 / 4 ( 2 h + k ) δ ; formistakes on { 111 } planes 3 ( 3 N ) 1 2 / 8 h δ if h ≥ k + l , 3 ( 3 N ) 1 2 / 4 ( h + k + l ) δ if h < k + l ; where δ is the probability of a mistake per unit length, h, k, l are the positive values of the indices of reflexion arranged in the order h ≥ k ≥ 1, and N = h 2 + k 2 + l 2 . When differences in interfacial energy are taken into account the apparent particle size for mistakes on {100} planes becomes 2 N 1 2 / { 2 ( h + k + l − u ) δ ′ + ( h + k + l + u ) δ ′ ′ } , where u is the impaired index, and that for mistakes on {110} planes becomes ( 2 N ) 1 2 / { 4 h δ ′ + 2 ( h + k ) δ ′ ′ } when ( 2 N ) 1 2 / { 2 ( h + k ) δ ′ + ( 3 h + k ) δ ′ ′ } when k or l is the unpaired index. All {111} interfaces have the same energy in AuCu 3 , so the expressions for mistakes on {111} planes are not altered.
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