The liquidus line and gibbs free energy of formation of a crystalline compound A m B n (c). II. Analysis of the liquidus
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T h e l i q u i d u s l i n e s o f I n S b , I n A s , G a S b , a n d G a A s a r e fit u s i n g t h e h e a t - o f - f u s i o n l i q u i d u s e q u a t i o n a n d s i x d i f f e r e n t m o d e l s f o r t h e l i q u i d p h a s e . F o l l o w i n g a n e a r l i e r p a p e r , t h e o v e r a l l fit i s j u d g e d s a t i s f a c t o r y o n l y w h e n the s t a n d a r d d e v i a t i o n b e t w e e n the c a l c u l a t e d a n d o b s e r v e d l i q u i d u s t e m p e r a t u r e s is e q u a l to o r less t h a n t h e p r e c i s i o n o f t h e e x p e r i m e n t a l t e m p e r a t u r e s a n d w h e n the e n t h a l p y a n d e n t r o p y of f o r m a t i o n o f t h e c o m p o u n d a r e c a l c u l a t e d c o r r e c t l y f r o m t h e p a r a m e t e r s of t h e l i q u i d u s f i t . T h e i d e a l , s t r i c t l y r e g u l a r , a n d q u a s i r e g u l a r m o d e l s f o r t h e l i q u i d p h a s e do not l e a d t o a s a t i s f a c t o r y o v e r a l l f i t f o r a n y o f the f o u r c o m p o u n d s . T h e q u a s i c h e m i c a l m o d e l is s a t i s f a c t o r y o n l y f o r InSb. T h e g e n e r a l i z e d l i q u i d p h a s e m o d e l g i v e n e a r l i e r a n d that c o r r e s p o n d i n g t o a M a r g u l e s e x p a n s i o n t r u n c a t e d a f t e r t h e c u b i c t e r m s a r e b o t h s a t i s f a c t o r y f o r InSb a n d I n A s . T h e y a r e not s a t i s f a c t o r y f o r GaSb a n d G a A s b u t , i n o u r o p i n i o n , t h i s i s m o r e l i k e l y due t o e r r o r s i n t h e e x p e r i m e n t a l v a l u e s f o r the e n t h a l p y a n d e n t r o p y of f o r m a t i o n f o r t h e s e c o m p o u n d s t h a n t o a n i n a d e q u a c y of the m o d e l s . I N a p r e v i o u s p a p e r ,1 h e r e a f t e r r e f e r r e d t o a s I , a t h e o r e t i c a l d i s c u s s i o n was g i v e n f o r t h e l i q u i d u s line of a c o m p o u n d AraBn(c) a n d a n a p p l i c a t i o n m a d e t o t h e InSb l i q u i d u s l i n e . In t h i s p a p e r we r e p o r t t h e m o r e e x t e n s i v e a p p l i c a t i o n o f t h e r e s u l t s g i v e n in I t o c o m p u t e r f i t s o f the l i q u i d u s l i n e s f o r I n S b , I n A s , G a S b , a n d G a A s u s i n g six d i f f e r e n t m o d e l s f o r t h e liquid phase. T w o t y p e s of c a l c u l a t i o n w e r e p e r f o r m e d f o r t h e p u r p o s e o f c o m p a r i s o n . In t h e f i r s t , a l l o f t h e a d j u s t a b l e p a r a m e t e r s a p p e a r i n g i n the e x p r e s s i o n s f o r t h e l i q u i d p h a s e a c t i v i t y c o e f f i c i e n t s w e r e f r e e t o fit t h e liquidus. They were v a r i e d u s i n g t h e s i m p l e x c o m p u t e r t e c h n i q u e 2 u n t i l a m i n i m u m was f o u n d in t h e s t a n d a r d deviation, a, b e t w e e n the l i q u i d u s t e m p e r a t u r e s calculated u s i n g the customary, heat-of-fusion liquidus e q u a t i
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