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MAGNETIC HYPERFINE INTERACTIONS IN Ni0.6Fe2.4-I - BORACITE
D. Bard, S. Constantinescu, I. Zheludev, I. Iarmuhamedov
To cite this version:
D. Bard, S. Constantinescu, I. Zheludev, I. Iarmuhamedov. MAGNETIC HYPERFINE INTERAC-
TIONS IN Ni0.6Fe2.4-I - BORACITE. Journal de Physique Colloques, 1980, 41 (C1), pp.C1-163-C1-
164. �10.1051/jphyscol:1980143�. �jpa-00219712�
JOURNAL DE PHYSIQUE Colioque C1, supplkrnent au n O 1, Tome 41, janvier 1980, page C1-163
MAGNETIC HYPERFINE INTERACTIONS IN N& 6Fe2. 4-1
-
BORACITE+ +
D. Bard, S . Constantinescu, I . S . Zheludev and I . N . Iarmuhamedov
I n s t i t u t e of Physics and l'e.chnoZogy of Materials, P. 0. Box 5207, Bucharest- Romania.
+
I n s t i t u t e of CrystaZ Zography, Moscm, USSR.I n t h e low t e m p e r a t u r e r e g i o n t h e N i 0 , 6 F e 2 , 4 B 7 0 , 3 1 i s an i m p r o p e r f e r r o e l e c - t r i c , h a v i n g f o u r v e c i n i t i e s A , B , C , O , c o r - r e s p o n d i n g t o 0 , 1 , 2 and r e s p e c t i v e l y 3Ni 2 +
n e i g h b a u r s a r o u n d 5 7 ~ e / 3 / , The aim o f t h i s p a p e r i s t o a n a l y s e t h e i n f l u e n c e o f
~ 1 ~ ' i o n s on t h e h y p e r f i n e p a r a m e t e r s o f t h e Mossbauer s p e c t r u m .
The Mossbauer m e a s u r e m e n t s c a r r i e d o u t a t 4 . 2 K e x h i b i t a v e r y complex s p e c - t r u m due t o t h e f o u r e q u a l l y w e i g h t e d s u b - l a t t i c e s a s s o c i a t e d t o e a c h v i c i n i t y , h a v i n g i n view t h e s t r u c t u r a l s i m i l a r i t y o f o u r s a m p l e w i t h Fe3B7OI3I o n e /2/. Each s u b l a t - t i c e c o r r e s p o n d s t o a combined m a g n e t i c d i p o l e - e l e c t r i c q u a d r u p o l e i n t e r a c t i o n ,
I n o r d e r t o f i t t h e e x p e r i m e n t a l s p e c - t r u m , t h e q u a d r u p o l e s p l i t t i n g s . w e i g h t s and c e n t e r s h i f t s f o r e a c h v i c f n i t y d e t e r - mined a t 35 K /I/ h a v e been u s e d , s u p p o s -
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Article published online by EDP Sciences and available at http://dx.doi.org/10.1051/jphyscol:1980143
C1-164 JOURNAL DB PHYSIQUE
m a g n e t i c a n i s o t r o p y and t h e s p i n s t r u c t u r e o f t h e b o r a c i t e , The l a s t o n e was d e t e r - mined by means o f n e u t r o n d i f f r a c t i o n mea- s u r e m e n t s on N i g - I - b o r a c i t e a s b e i n g O M = g o 0 , q,,, =\L 6') 90' r e l a t i v e t o t h e o r t h o r h o m b i c a x i s /3/.
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100 cm-I a n d R/A((-10,20].T h i s i m p l i e s t h a t EIA2, B21 s t a t e r e p r a - s e n b s t h e e l e c t r o n i c g r o u n d s t a t e . The d i f - f e r e n t v a l u e s o f H e f f f o r e a c h o f t h e A , B , C , D v i c i n i t i e s may b e o b t a i n e d f r o m t h e v a - l u e s of w a n d 5271. The f o u r t h s u b l a t t i c e e b s e r v e d i n o u r s a m p l e c o u l d a p p e a r f r o m a s p i n c o n f i g u r a t i o n w i t h qM 90'.
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