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Crystal growth of metal-phosphorus-sulfur compounds by vapor transport
Mat. Res. Bull. Vol. 5, pp. 419-424, 1970. Pergamon Press, Inc. Printed in the United States.
CRYSTA L GROWTH
O F M E T A L- PHOS P H O R U S - S U L F U R C O M P O U N D S B Y V A P O R T RA NS P O R T
R. Nitsche Kristallographisches Institut, University of Freiburg, Freiburg, Germany and P. Wild Laboratories-RCA Ltd., Ztlrich, Switzerland
(Received April 6, 1970; Communicated by W. W. Tyler) ABSTRACT Single crystals of the thio-phosphates: Cu3PS4, InPS4, GAPS4, BiPS4 and the thio-hypophosphates Sn2P2S6, Cd2P2S6, Fe2P2S6 and Mn2P2S6 were grown in sizes up to I0 mm by vapour transport with iodine. Lattice parameters and space groups are given.
Introduction Chemical transport (1) with halogens has developed into a useful technique for growing single crystals of high-melting or decomposing binary and ternary chalcogenides [e. g. ZnS, CdIn2S 4 (2)] and pnictides [e. g. GaP (3), CdSiP 2 (4)].
We have found that single crystals of many metal-phosphorus-
sulfur compounds--some previously unknown--can also be grown by iodine transport from the vapour phase.
This paper describes growth experiments
and gives crystallographic data derived from Weissenberg and precession photographs. Metal-arsenic-sulfur compounds occur frequently as minerals.
Sim-
ple phosphorus analogues (e. g. Cu3PS 4 which is isomorphous to enargite, Cu3AsS 4) have already been prepared in the last century by Glatzel (5) and Ferrand (6) by reacting metal-halides or -sulfides with P2S5 . The polyvalent properties of phosphorus make it probable that various types of compounds 419
420
CRYSTAL GROWTH BY VAPOUR TRANSPORT
Vol. 5, No. 6
can exist in M e - P - S - S y s t e m s , ranging from mixed anion compounds with p - 3 to thio-phosphates with p+5.
In recent y e a r s , s e v e r a l new M e - P - S com-
pounds have been found, some having interesting physical properties.
Kamsu
Kom, et al. (7) described CUPS, Hulliger (8-10) the a r s e n o p y r i t e analogue FePS, the compounds REPS (RE = Gd, Pr, Tb, Dy, Y, E r ) a n d ThPS and UPS.
F r o m the l a t t e r he obtained single c r y s t a l s by iodine and bromine t r a n s -
port.
Donahue and Bierstedt (11) found superconductivity in NbPS and pre-
pared TaPS and NbPSe.
Hahn, Klingen and E u l e n b e r g e r (12-14) reported the II s y n t h e s i s of compounds Me 2 P2S6 (Me I I = Zn, Cd, Mn, Fe, Co, Ni, V ) a n d c l a s s i f y these from s t r u c t u r a l considerations as thio-hypodiphosphates with P - P bonds in P2S6 s t r u c t u r a l units.
F e r r a r i and Cavalca (15) determined
the s t r u c t u r e of copper thiophosphate Cu3PS4, Weiss and Schaefer (16-18) the s t r u c t u r e s of the thio-phosphates AlPS4, BPS 4 and K3PS 4. C r y s t a l Growth and C h a r a c t e r i z a t i o n Stoichiometric amounts of the constituting elements ("five nine" purity, total amount 4 g) and about 100 mg iodine were sealed into quartz ampoules (length = 10, ~ = 1, 5 cm) and brought to reaction.
Then the ampoule was
placed into a horizontal t e m p e r a t u r e gradient, the charge being in the hot (T1), c r y s t a l s growing in the cold end (T2). F o r details of the method see (19).
Average growth t i m e s were 100 hours.
The c r y s t a l s were c h a r a c t e r i z e d by pow-
d e r and s i n g l e - c r y s t a l photographs, e l e c t r o n - m i c r o p r o b e and wet chemical analysis. argon.
They were also heated in a Mettler t h e r m o a n a l y z e r in a s t r e a m of
Except for Cu3PS 4 which appeared to melt around 960°C, the thio-
phosphates (thio-hypophosphates)decompose between 500-700 ° into the metalsulfides and volatile P2S5(P2S4).
F r o m the weight loss after completed de-
composition the original composition can be inferred. Cu3PS 4 (T 1 = 850 °, T 2 = 800 ° ) T r a n s p a r e n t , yellowish-brown p r i s m s up to 4 x 4 x 8 mm, bound by (100), (110) and (010) faces.
Analysis (theoretical values in brackets) in
weight %: Cu: 53.8 (54.5); P: 9.3 (8.9); S: 35.8 (36.7). g/cc.
D e n s i t y p = 3.77
Lattice: orthorhombic, a = 6.43, b = 7.55, c = 6. 12 A.
These values
a r e in close a g r e e m e n t with the powder data of F e r r a r i and Cavalca (15) who
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C R Y S T A L GROWTH BY V A P O U R T R A N S P O R T
s y n t h e s i z e d p o l y c r y s t a l l i n e Cu3PS 4 f r o m Cu2S and P2S5 .
421
Our observed re-
f l e c t i o n c o n d i t i o n s (hO~: A~+ h = 2n) a g r e e w i t h t h e s p a c e g r o u p P m n 2 1 = C 7 2v p r o p o s e d by t h e s e a u t h o r s . InPS 4 (T 1 = 640 o, T 2 - - 580 o) Transparent, polyhedra.
c o l o r l e s s n e e d l e s u p to 0. 5 x 0 . 5 x 15 m m , s o m e t i m e s
D e c o m p o s i t i o n at 650 °.
( l l . 3); S: 46. 7 (46. 8) w e i g h t %.
Analysis:
p = 3.16 g/cc.
In: 4 1 . 7 (41.9); P: I I . 6 This--hitherto unknown--
c o m p o u n d h a s a b o d y - c e n t e r e d t e t r a g o n a l l a t t i c e , a = 5 . 5 9 , c = 9 . 0 0 A., with two f o r m u l a u n i t s p e r cell.
T h e e x i s t e n c e of a p o s i t i v e p i e z o - e f f e c t a n d t h e 2 r e f l e c t i o n c o n d i t i o n s d e t e r m i n e the s p a c e g r o u p to I/~ = S 4. N e e d l e a x i s is [Ill].
T h e c r y s t a l s a r e o f t e n t w i n n e d a l o n g t h i s axis.
GaPS 4 (T 1 = 450 ° , T 2 = 430 ° ) E x t r e m e l y thin, c o l o r l e s s , p o s i t i o n at 460 ° .
m i c a - l i k e p l a t e s up to 5 x 5 m m .
Decom-
No f u r t h e r d a t a a v a i l a b l e at p r e s e n t .
BiPS 4 (T 1 = 660 °, T 2 = 610 °) E l o n g a t e d , d a r k r e d p r i s m s u p to 3 x 3 x 6 m m . 620 °.
Analysis:
4.13 g/cc.
D e c o m p o s i t i o n at
Bi: 5 7 . 3 (56.8); P: 9 . 3 (8.4); S: 3 3 . 4 (34.9) w e i g h t % ,
p =
T h e e x i s t e n c e of t h i s c o m p o u n d h a s b e e n r e p o r t e d by G l a t z e l (5)
b u t no c r y s t a l l o g r a p h i c d a t a w e r e known.
We find a n o r t h o r h o m b i c l a t t i c e ,
a = 5 . 2 4 , b = 5 . 5 0 , c = 9 . 7 5 A . , with two f o r m u l a u n i t s p e r cell. s y m b o l is m m m P ,
Diffraction
i . e . p o s s i b l e s p a c e g r o u p s a r e P222; P m m 2 ; P m m m .
c o n d u c t i v i t y of the c r y s t a l s w a s too h i g h f o r m e a s u r i n g a p i e z o - e f f e c t .
The The
a x i s of the p r i s m s is [110]. S_n2_P2S6 (W1 = 600 °, T 2 = 630 ° ) O r a n g e , t r a n s p a r e n t p o l y h e d r a up to 5 x 5 x 5 m m . 670 °.
Analysis:
p = 3.32 g/cc.
D e c o m p o s i t i o n at
Sn: 4 9 . 8 (48.3); P: 10. 9 (12.6); S: 3 9 . 3 (39.1) w e i g h t %. T h i s c o m p o u n d , not r e p o r t e d so f a r , a p p a r e n t l y b e l o n g s to
the c l a s s of t h i o - h y p o p h o s p h a t e s d i s c o v e r e d by Hahn and c o w o r k e r s (13-15). We f i n d a m o n o c l i n i c l a t t i c e :
a = 6.43;b
T h e d i f f r a c t i o n s y m b o l is 1 2 / m l P c .
= 7.47; c = 1 1 . 0 3 A . ;
fi = 1 2 2 . 2 ° .
T h i s , t o g e t h e r with a p o s i t i v e p i e z o 2 e f f e c t , d e t e r m i n e s the s p a c e g r o u p to Pc = C s.
422
CRYSTAL GROWTH BY VAPOUR TRANSPORT
Vol. 5, No. 6
F.__e2_P2_S6 (T 1 = 670 °, T 2 = 620 ° ) Black, flexible, hexagonal plates up to 0. 1 x 10 x 10 mm. Mn2_P2~6 (W1 = 670 °, W2 = 620 °) T r a n s p a r e n t green, hexagonal plates up to 0. 1 x 10 x 10 mm. C.__d2_P2~6 (W1 = 630 ° , T 2 = 600 ° ) T r a n s p a r e n t , c o l o r l e s s plates up to 0. 1 x 4 x 4 mm. The thio-hypophosphates 6, 7, 8 have been d e s c r i b e d by Hahn et al. (13, 14).
X - r a y powder d i a g r a m s r e v e a l e d the same p s e u d o - r h o m b o h e d r a l
lattices as found by these authors. Conclusion The feasibility to grow c r y s t a l s of thio-phosphates and thiohypophosphates by iodine t r a n s p o r t has been d e m o n s t r a t e d . Cu3PS4, InPS4, BiPS 4 and Sn2P2S 6 a r e given.
Lattice data of
It is believed that by c a r e -
fully studying the f o r m a t i o n conditions n u m e r o u s other Me- P-S com pounds can be grown.
Detailed s t r u c t u r a l investigations a r e in progress. Acknowledgment
We a r e indebted to R. Diehl for d i s c u s s i o n s on the space group of InPS 4. References 1. H. Schaefer, Chemical T r a n s p o r t Reactions. York (1964).
Academic P r e s s , New
2. R. Nitsche, H. U. BSlsterli and M. L i c h t e n s t e i g e r , J. Phys. Chem. Solids 21, 199 (1961). 3. H. G. G r i m m e i s , A. Rabenau and H. Koelmans, J. Appl. Phys. 3_~2, 2133 (1961). 4. J. A. Valov and R. L. Plecko, Kristall und Technik 2, 535 (1967). 5. E. Glatzel, Z. anorg. Chem. 4, 186 (1893). 6. L. F e r r a n d , Ann. Chim. Phys. [7] I_.~7, 388 (1899). 7. J. Kamsu Kom, J. Flahaut and L. Domange, Compt. Rend. 255, 701 (1962). 8. F. Hulliger, Helv. Phys. Acta 32, 615 (1959).
Vol. 5, No.
6
CRYSTAL
GROWTH
BY VAPOUR
TRANSPORT
423
9. F. Hulliger, Nature 219, 373 (1968). 10. F. Hulliger, J. L e s s - c o m m o n Met. 1_.66, 113 (1968). 11. P. C. Donahue and P. E. Bierstedt, Inorg. Chem. 8, 2690 (1969). 12. H. Hahn and W. Klingen, Naturwiss. 52, 494 (1965). 13. W. Klingen, G. Eulenberger and H. Hahn, Naturwiss. 55, 229 (1968). 14. W. Klingen, G. Eulenberger and H. Hahn, Meeting on Transition Metal Compounds, Oslo, Norway (1969). 15. A. F e r r a r i and L. Cavalca, Gazz. Chim. Ital. 7-2, 283 (1948). 16. A. Weiss and H. Schaefer, Naturwiss. 4...77,495 (1960). 17. A. Weiss and H. Schaefer, Z. Naturforsch. 18b, 81 (1963). 18. H. Schaefer, G. Schaefer and A. Weiss, Z. Naturforsch. 20b, 811 (1965). 19. R. Nitsche, F o r t s c h r . Min. 4..4.4, 231 (1967).
CRYSTA L GROWTH
O F M E T A L- PHOS P H O R U S - S U L F U R C O M P O U N D S B Y V A P O R T RA NS P O R T
R. Nitsche Kristallographisches Institut, University of Freiburg, Freiburg, Germany and P. Wild Laboratories-RCA Ltd., Ztlrich, Switzerland
(Received April 6, 1970; Communicated by W. W. Tyler) ABSTRACT Single crystals of the thio-phosphates: Cu3PS4, InPS4, GAPS4, BiPS4 and the thio-hypophosphates Sn2P2S6, Cd2P2S6, Fe2P2S6 and Mn2P2S6 were grown in sizes up to I0 mm by vapour transport with iodine. Lattice parameters and space groups are given.
Introduction Chemical transport (1) with halogens has developed into a useful technique for growing single crystals of high-melting or decomposing binary and ternary chalcogenides [e. g. ZnS, CdIn2S 4 (2)] and pnictides [e. g. GaP (3), CdSiP 2 (4)].
We have found that single crystals of many metal-phosphorus-
sulfur compounds--some previously unknown--can also be grown by iodine transport from the vapour phase.
This paper describes growth experiments
and gives crystallographic data derived from Weissenberg and precession photographs. Metal-arsenic-sulfur compounds occur frequently as minerals.
Sim-
ple phosphorus analogues (e. g. Cu3PS 4 which is isomorphous to enargite, Cu3AsS 4) have already been prepared in the last century by Glatzel (5) and Ferrand (6) by reacting metal-halides or -sulfides with P2S5 . The polyvalent properties of phosphorus make it probable that various types of compounds 419
420
CRYSTAL GROWTH BY VAPOUR TRANSPORT
Vol. 5, No. 6
can exist in M e - P - S - S y s t e m s , ranging from mixed anion compounds with p - 3 to thio-phosphates with p+5.
In recent y e a r s , s e v e r a l new M e - P - S com-
pounds have been found, some having interesting physical properties.
Kamsu
Kom, et al. (7) described CUPS, Hulliger (8-10) the a r s e n o p y r i t e analogue FePS, the compounds REPS (RE = Gd, Pr, Tb, Dy, Y, E r ) a n d ThPS and UPS.
F r o m the l a t t e r he obtained single c r y s t a l s by iodine and bromine t r a n s -
port.
Donahue and Bierstedt (11) found superconductivity in NbPS and pre-
pared TaPS and NbPSe.
Hahn, Klingen and E u l e n b e r g e r (12-14) reported the II s y n t h e s i s of compounds Me 2 P2S6 (Me I I = Zn, Cd, Mn, Fe, Co, Ni, V ) a n d c l a s s i f y these from s t r u c t u r a l considerations as thio-hypodiphosphates with P - P bonds in P2S6 s t r u c t u r a l units.
F e r r a r i and Cavalca (15) determined
the s t r u c t u r e of copper thiophosphate Cu3PS4, Weiss and Schaefer (16-18) the s t r u c t u r e s of the thio-phosphates AlPS4, BPS 4 and K3PS 4. C r y s t a l Growth and C h a r a c t e r i z a t i o n Stoichiometric amounts of the constituting elements ("five nine" purity, total amount 4 g) and about 100 mg iodine were sealed into quartz ampoules (length = 10, ~ = 1, 5 cm) and brought to reaction.
Then the ampoule was
placed into a horizontal t e m p e r a t u r e gradient, the charge being in the hot (T1), c r y s t a l s growing in the cold end (T2). F o r details of the method see (19).
Average growth t i m e s were 100 hours.
The c r y s t a l s were c h a r a c t e r i z e d by pow-
d e r and s i n g l e - c r y s t a l photographs, e l e c t r o n - m i c r o p r o b e and wet chemical analysis. argon.
They were also heated in a Mettler t h e r m o a n a l y z e r in a s t r e a m of
Except for Cu3PS 4 which appeared to melt around 960°C, the thio-
phosphates (thio-hypophosphates)decompose between 500-700 ° into the metalsulfides and volatile P2S5(P2S4).
F r o m the weight loss after completed de-
composition the original composition can be inferred. Cu3PS 4 (T 1 = 850 °, T 2 = 800 ° ) T r a n s p a r e n t , yellowish-brown p r i s m s up to 4 x 4 x 8 mm, bound by (100), (110) and (010) faces.
Analysis (theoretical values in brackets) in
weight %: Cu: 53.8 (54.5); P: 9.3 (8.9); S: 35.8 (36.7). g/cc.
D e n s i t y p = 3.77
Lattice: orthorhombic, a = 6.43, b = 7.55, c = 6. 12 A.
These values
a r e in close a g r e e m e n t with the powder data of F e r r a r i and Cavalca (15) who
Vol. 5, No. 6
C R Y S T A L GROWTH BY V A P O U R T R A N S P O R T
s y n t h e s i z e d p o l y c r y s t a l l i n e Cu3PS 4 f r o m Cu2S and P2S5 .
421
Our observed re-
f l e c t i o n c o n d i t i o n s (hO~: A~+ h = 2n) a g r e e w i t h t h e s p a c e g r o u p P m n 2 1 = C 7 2v p r o p o s e d by t h e s e a u t h o r s . InPS 4 (T 1 = 640 o, T 2 - - 580 o) Transparent, polyhedra.
c o l o r l e s s n e e d l e s u p to 0. 5 x 0 . 5 x 15 m m , s o m e t i m e s
D e c o m p o s i t i o n at 650 °.
( l l . 3); S: 46. 7 (46. 8) w e i g h t %.
Analysis:
p = 3.16 g/cc.
In: 4 1 . 7 (41.9); P: I I . 6 This--hitherto unknown--
c o m p o u n d h a s a b o d y - c e n t e r e d t e t r a g o n a l l a t t i c e , a = 5 . 5 9 , c = 9 . 0 0 A., with two f o r m u l a u n i t s p e r cell.
T h e e x i s t e n c e of a p o s i t i v e p i e z o - e f f e c t a n d t h e 2 r e f l e c t i o n c o n d i t i o n s d e t e r m i n e the s p a c e g r o u p to I/~ = S 4. N e e d l e a x i s is [Ill].
T h e c r y s t a l s a r e o f t e n t w i n n e d a l o n g t h i s axis.
GaPS 4 (T 1 = 450 ° , T 2 = 430 ° ) E x t r e m e l y thin, c o l o r l e s s , p o s i t i o n at 460 ° .
m i c a - l i k e p l a t e s up to 5 x 5 m m .
Decom-
No f u r t h e r d a t a a v a i l a b l e at p r e s e n t .
BiPS 4 (T 1 = 660 °, T 2 = 610 °) E l o n g a t e d , d a r k r e d p r i s m s u p to 3 x 3 x 6 m m . 620 °.
Analysis:
4.13 g/cc.
D e c o m p o s i t i o n at
Bi: 5 7 . 3 (56.8); P: 9 . 3 (8.4); S: 3 3 . 4 (34.9) w e i g h t % ,
p =
T h e e x i s t e n c e of t h i s c o m p o u n d h a s b e e n r e p o r t e d by G l a t z e l (5)
b u t no c r y s t a l l o g r a p h i c d a t a w e r e known.
We find a n o r t h o r h o m b i c l a t t i c e ,
a = 5 . 2 4 , b = 5 . 5 0 , c = 9 . 7 5 A . , with two f o r m u l a u n i t s p e r cell. s y m b o l is m m m P ,
Diffraction
i . e . p o s s i b l e s p a c e g r o u p s a r e P222; P m m 2 ; P m m m .
c o n d u c t i v i t y of the c r y s t a l s w a s too h i g h f o r m e a s u r i n g a p i e z o - e f f e c t .
The The
a x i s of the p r i s m s is [110]. S_n2_P2S6 (W1 = 600 °, T 2 = 630 ° ) O r a n g e , t r a n s p a r e n t p o l y h e d r a up to 5 x 5 x 5 m m . 670 °.
Analysis:
p = 3.32 g/cc.
D e c o m p o s i t i o n at
Sn: 4 9 . 8 (48.3); P: 10. 9 (12.6); S: 3 9 . 3 (39.1) w e i g h t %. T h i s c o m p o u n d , not r e p o r t e d so f a r , a p p a r e n t l y b e l o n g s to
the c l a s s of t h i o - h y p o p h o s p h a t e s d i s c o v e r e d by Hahn and c o w o r k e r s (13-15). We f i n d a m o n o c l i n i c l a t t i c e :
a = 6.43;b
T h e d i f f r a c t i o n s y m b o l is 1 2 / m l P c .
= 7.47; c = 1 1 . 0 3 A . ;
fi = 1 2 2 . 2 ° .
T h i s , t o g e t h e r with a p o s i t i v e p i e z o 2 e f f e c t , d e t e r m i n e s the s p a c e g r o u p to Pc = C s.
422
CRYSTAL GROWTH BY VAPOUR TRANSPORT
Vol. 5, No. 6
F.__e2_P2_S6 (T 1 = 670 °, T 2 = 620 ° ) Black, flexible, hexagonal plates up to 0. 1 x 10 x 10 mm. Mn2_P2~6 (W1 = 670 °, W2 = 620 °) T r a n s p a r e n t green, hexagonal plates up to 0. 1 x 10 x 10 mm. C.__d2_P2~6 (W1 = 630 ° , T 2 = 600 ° ) T r a n s p a r e n t , c o l o r l e s s plates up to 0. 1 x 4 x 4 mm. The thio-hypophosphates 6, 7, 8 have been d e s c r i b e d by Hahn et al. (13, 14).
X - r a y powder d i a g r a m s r e v e a l e d the same p s e u d o - r h o m b o h e d r a l
lattices as found by these authors. Conclusion The feasibility to grow c r y s t a l s of thio-phosphates and thiohypophosphates by iodine t r a n s p o r t has been d e m o n s t r a t e d . Cu3PS4, InPS4, BiPS 4 and Sn2P2S 6 a r e given.
Lattice data of
It is believed that by c a r e -
fully studying the f o r m a t i o n conditions n u m e r o u s other Me- P-S com pounds can be grown.
Detailed s t r u c t u r a l investigations a r e in progress. Acknowledgment
We a r e indebted to R. Diehl for d i s c u s s i o n s on the space group of InPS 4. References 1. H. Schaefer, Chemical T r a n s p o r t Reactions. York (1964).
Academic P r e s s , New
2. R. Nitsche, H. U. BSlsterli and M. L i c h t e n s t e i g e r , J. Phys. Chem. Solids 21, 199 (1961). 3. H. G. G r i m m e i s , A. Rabenau and H. Koelmans, J. Appl. Phys. 3_~2, 2133 (1961). 4. J. A. Valov and R. L. Plecko, Kristall und Technik 2, 535 (1967). 5. E. Glatzel, Z. anorg. Chem. 4, 186 (1893). 6. L. F e r r a n d , Ann. Chim. Phys. [7] I_.~7, 388 (1899). 7. J. Kamsu Kom, J. Flahaut and L. Domange, Compt. Rend. 255, 701 (1962). 8. F. Hulliger, Helv. Phys. Acta 32, 615 (1959).
Vol. 5, No.
6
CRYSTAL
GROWTH
BY VAPOUR
TRANSPORT
423
9. F. Hulliger, Nature 219, 373 (1968). 10. F. Hulliger, J. L e s s - c o m m o n Met. 1_.66, 113 (1968). 11. P. C. Donahue and P. E. Bierstedt, Inorg. Chem. 8, 2690 (1969). 12. H. Hahn and W. Klingen, Naturwiss. 52, 494 (1965). 13. W. Klingen, G. Eulenberger and H. Hahn, Naturwiss. 55, 229 (1968). 14. W. Klingen, G. Eulenberger and H. Hahn, Meeting on Transition Metal Compounds, Oslo, Norway (1969). 15. A. F e r r a r i and L. Cavalca, Gazz. Chim. Ital. 7-2, 283 (1948). 16. A. Weiss and H. Schaefer, Naturwiss. 4...77,495 (1960). 17. A. Weiss and H. Schaefer, Z. Naturforsch. 18b, 81 (1963). 18. H. Schaefer, G. Schaefer and A. Weiss, Z. Naturforsch. 20b, 811 (1965). 19. R. Nitsche, F o r t s c h r . Min. 4..4.4, 231 (1967).