[Au_2(C_(26)H_(48)P_2h](PF_6)_2, M_r = 1529·1, tetragonal, P4n2, ɑ= 15·917 (5), c = 12-448 (1) A, V = 3154 (1) A3

, Z = 2, Dx = 1·61 g cm^(-3), λ(Mo Ka) = 0·71073 A, μ = 50·1 cm^(-1), F(000) = 1528, room temperature (297 K), R = 0·064 for 3525 reflections with F/_o^2 > 0,0·038 for 2440 with F/_o^2 > 3σ(F/_o^2). This [Au_2(C_26)H_(48)P_2)_2] (PF_6)_2 compound shows a strong luminescence in the solid state at 77 K. The cation consists of two Au atoms joined by two bis (dicyclohexylphosphino )ethane links, with one Au atom and one half of a link being the asymmetric unit. The Au-Au distance [2·936 (1) Å] is only slightly longer than the 2·884 Å found in gold metal, indicative of substantial metal-metal bonding

Gray, H. B.

Marsh, R. E.

McCleskey, T. M.

Schaefer, W. P.

Caltech Authors - Main

VIOSSAT, NGUYEN-HUY DUNG, ROBERT, LANCELOT ET ROBBA 2553 
Tableau 2. Distances interatomiques (A) et angles (0 ) 
Rh-Rh' 2,3829 (6) 0(1)-C(I) 1,260 (5) 
Rh-0(1) 2,031 (3) C(l}-C(2) 1,498 (7) 
Rh-0(2) 2,043 (3) C(l)-D(4') 1,266 (5) 
Rh-0(3) 2,030 (3) 0(2)-C(3) 1,265 (5) 
Rh-0(4) 2,038 (3) C(3}-C(4) 1,495 (8) 
Rh-N(l3) 2,241 (4) C(3)-D(3') 1,270 (5) 
S(ll)-c(l2 1,722 (4) S(2 I )-c(22) 1,716 (5) 
S(l l)-c(l5) 1,730(5) S(2 I )-c(25) 1,699 (7) 
C(l2}-N(J3) 1,310 (5) C(22)-C(23) 1,389 (7) 
C(l2)-N(28) 1,360(6) C(22)-C(26) 1,461 (7) 
N(l3)-c(14) 1,365 (6) C(23)-c(24) 1,390 (8) 
C(l4)-c(l5) 1,332 (7) C(24)-c(25) 1,356 (9) 
C(l5)-N(16) 1,434 (6) C(26)-D(27) 1,219 (6) 
N(l6)-D(l7) 1,219 (6) C(26)-N(28) 1,369 (6) 
N(l6)-D(l8) 1,223 (6) 
C(30)-Cl(31) 1,753 (9) C(30)-Cl(32) 1,753 (9) 
Rh'-Rh-0(1) 88,52 (9) O(l)-Rh-N(J3) 90,9 (1) 
Rh;-Rh-0(2) 88,50 (9) 0(2)-Rh-0(3) 175,9 (1) 
Rh;-Rh-0(3) 87,54 (9) 0(2)-Rh-0(4) 89,3 (I) 
Rh'-Rh-0(4) 87,66 (9) 0(2)-Rh-N(13) 93,0 (I) 
Rh;-Rh-N(J3) 178,4 (I) 0(3)-Rh-0(4) 91,6 (I) 
0(1)-Rh-0(2) 90,0 (I) 0(3)-Rh-N(l 3) 90,9 (I) 
0(1)-Rh-0(3) 88,8 (I) 0(4)-Rh-N(l3) 92,9 (I) 
0(1)-Rh-0(4) 176,1 (I) 
0(1)-C(l)-C(2) 117,8 (5) C(4)-C(3)-D(3') 117,9 (5) 
0( 1 )-C( I )-0(4') 125,7 (4) Rh-0( I )-C( I) 118,8 (3) 
C(2)-c(l)-D(4') 116,5 (5) Rh-0(2)-C(3) 118,9 (3) 
0(2)-C(3)-C( 4) 117,8 (5) Rh-0(3)-c(3') 120,5 (3) 
0(2)-C(3)-0(3') 124,4(4) Rh-0(4)-c(I') 119,3 (3) 
Rh-N(l3)-c(l2) 127,1 (3) 0(17)-N(l6)-0(18) 125,2 (5) 
Rh-N(l3)-C(l4) 122,6 (3) C(22)-S(2 I )-c(25) 91,6 (3) 
C(l2)-S(l l)-c(15) 86,5 (2) S(2 I )-C(22)-C(23) 110,9 (4) 
S(l l)-C(l2)-N(J3) 116,3 (4) S(21 )-c(22)-c(26) 124,2 (4) 
S(l l)-C(l2)-N(28) 123,2 (3) C(23)-C(22)-c(26) 124,9 (5) 
N(l3)-C(l2)-N(28) 120,5 (4) C(22)-C(23)-c(24) 112,0 (5) 
S(ll)-C(l5)-c(l4) 112,6 (4) C(23)-C(24)-C(25) 113,3 (6) 
S(l l)-C(l5)-N(l6) 121,4 (4) C(24 )-C(25)-S(2 I) 112,1 (5) 
C( 12)-N( 13)-C( 14) 110,2 (4) C(22)-C(26)-D(27) 123,0 (4) 
N( 13)-C( 14)-C(l 5) 114,3 (5) C(22)-C(26)-N(28) 117,8 (4) 
C(l4)-c(l5)-N(l6) 125,9 (5) 0(27)-C(26)-N(28) 119,2 (5) 
C(l5)-N(l6)-D(J 7) 118,2 (5) C(12)-N(28)-C(26) 124,2 (4) 
C(15)-N(16)-D(18) 116,6 (5) 
Cl(3 I )-c(30)-cl(32) 103,0 (9) 
Code de symetrie: (i) l - x, l - y, l - z. 
Acta Cryst. (1991). C47, 2553-2556 
L'etude radiocristallographique a montre que la 
structure dinucleaire de !'acetate de rhodium(II) est 
conservee apres reaction avec le tenonitrozole et que 
celui-ci est lie au rhodium par l'intermediaire de 
l'atome d'azote N(l 3) du groupement thiazole. 
Cependant la conformation du ligand differe de celle 
observee dans la molecule du tenonitrozole libre. 
References 
CARRUTHERS, J. R. & WATKIN, D. J. (1984). CRYSTALS. Chemi-
cal Crystallography Laboratory, Univ. d'Oxford, Angleterre. 
CHIBBER, R., STRATFORD, I. J., AHMED, I., ROBBINS, A. B., GooD-
GAME, D. & LEE, B. (l 984). Int. J. Radial. Biol. Phys. 10, 
1213-1215. 
COTTON, F. A. & FELTHOUSE, T. R. (1981). lnorg. Chem. 20, 
600-608. 
ERCK, A., RAINEN, L., WHILEYMAN, J., CHANG, I. M., KIMBALL, 
A. P. & BEAR, J. (1974). Proc. Soc. Exp. Biol. Med. 145, 
1278-1283. 
FARRELL, N., VARGAS, M. 0., MASCARENHAS, Y. A. & GAMBARD· 
ELLA, M. T. (1987). lnorg. Chem. 26, 1426-1429. 
GooDGAME, D. M. L., LAWRENCE, A. S., SLAWIN, A. M. Z., 
WILLIAMS, D. J. & STRATFORD, I. J. (1986). lnorg. Chim. Acta, 
125, 143-149. 
HOWARD, R. A., KIMBALL, A. P. & BEAR, J. L. (1979). Cancer Res. 
39, 2568-2573. 
JOHNSON, C. K. (1976). ORTEPII. Rapport ORNL-5138. Oak 
Ridge National Laboratory, Tennessee, EU. 
KoH, Y. B. & CHRISTOPH, G. G. (1978). lnorg. Chem. 17, 2590-
2596. 
MAIN, P., FISKE, S. J., HULL, S. E., LESSINGER, L., GERMAIN, G., 
DECLERCQ, J.-P. & WooLFSON, M. M. (1982). MULTANl 1182. 
A System of Computer Programs for the Automatic Solution of 
Crystal Structures from X-ray Diffraction Data. Univ. de York, 
Angleterre, et de Louvain, Belgique. 
NGUYEN-HUY DUNG, VIOSSAT, B., LANCELOT, J.C. & ROBBA, M. 
(1986). Chem. Pharm. Bull. 34, 951-956. 
VIOSSAT, B., NGUYEN-HUY DUNG, LANCELOT, J.C., ROBERT, F. & 
ROBBA, M. (1987). Chem. Pharm. Bull. 35, 2419-2425. 
WALKER, N. & STUART, D. (1983). Acta Cryst. A39, 159-166. 
A Luminescent Gold Complex: Bis-µ-(bis( dicyclohexylphosphino )ethane-P ,P')-digold 
Bis(hexafluorophosphate) 
BY WILLIAM P. SCHAEFER, RICHARD E. MARSH, T. MARK MCCLESKEY AND HARRY B. GRAY 
Division of Chemistry and Chemical Engineering* and The Beckman Institute, Mail Code 139-74, California 
Institute of Technology, Pasadena, California 91125, USA 
(Received 26 February 1991; accepted 25 June 1991) 
Abstract. [Au2(C26H4sP2h](PF6)2, Mr= 1529·1, 
tetragonal, P4n2, a= 15·917 (5), c = 12-448 (1) A, V 
* Contribution No. 8403. 
0 I 08-270 I /9 I /122553-04$03.00 
= 3154 (1) A3, Z = 2, Dx = 1 ·61 g cm- 3, J\(Mo Ka) 
= O· 71073 A, µ = 50· 1 cm - I, F(OOO) = 1528, room 
temperature (297 K), R = 0·064 for 3525 reflections 
with F/ > 0, 0·038 for 2440 with F/ > 3u(F/). This 
© 1991 International Union of Crystallography 
2554 
compound shows a strong luminescence in the solid 
state at 77 K. The cation consists of two Au atoms 
joined by two bis( dicyclohexylphosphino )ethane 
links, with one Au atom and one half of a link being 
the asymmetric unit. The Au-Au distance 
[2·936 (1) A] is only slightly longer than the 2·884 A 
found in gold metal, indicative of substantial metal-
metal bonding. 
Introduction. Several gold dimers have been reported 
to luminesce in the solid state (Khan, Fackler, King, 
Wang & Wang, 1988; Che, Wong, Lai & Kwong, 
1989; King, Wang, Khan & Fackler, 1989) with 
emission maxima from 456 to 593 nm and excited-
state lifetimes from 0· 1 to 24 µ s. At least two of 
these dimers have been reported to emit at room 
temperature in solution (Che et al., 1989; King et al., 
1989); the title compound { Au[bis-1,2-dicyclohexyl-
phosphino )ethane ]}i(PF 6) 2 was made in order to 
investigate the role of the Au-Au interaction in the 
dimer photophysics. The compound luminesces 
( 489 nm) in the solid state at 77 K but not at room 
temperature; it appears that the emission is a 
property of the AuP 2 monomeric unit, with the 
Au-Au interaction playing a lesser role. We are 
continuing this work with other gold dimers and 
related monomeric complexes. 
Experimental. This material was synthesized by 
adding one equivalent of the chelating phosphine 
ligand to 50 ml of argon-purged CH3CN containing 
150 mg of (Cl)Au(tetrahydrothiophene), which was 
prepared according to the literature procedure 
(Uson, Laguna & Vicente, 1977). After stirring for 
1 h the solvent was removed under reduced pressure. 
Metathesis to the PF6 - salt was accomplished by 
dissolving the Cl - salt in 30 ml of a 70/30 mixture of 
MeOH/H20 and then adding excess NH4PF6 to pre-
cipitate the PF 6 salt. The white PF 6 salt was collected 
by vacuum filtration; crystals for X-ray diffraction 
were grown by recrystallization from CH3CN/Et20. 
Crystal: square prism with cross section 0·26 x 
O· 26 mm, O· 3 mm long with skewed ends. CAD-4 
diffractometer; w scans; cell dimensions from 25 
reflections with 39 < 28 < 43°; no absorption correc-
tion (µrmax = l ·2, two data sets merged satisfacto-
rily); (sin(}/ A)max = 0·66 A - 1; data collected to 28 = 
56°, h from 0 to 21, k from 0 to 21, l from -16 to 16; 
three standard reflections, 230, 140 and 222, showed 
no variations greater than expected from counting 
statistics; 8221 reflections measured, 3805 indepen-
dent; goodness of fit for merging l ·08 {GOFhkl = 
[Inw(F;(hkl) - F;v(hkl))2/(n - 1 )]112 for n observations 
of reflection hkl; GOFmerge = [Imw(GOFhkt)2/m] 112, 
for m reflections with more than one contributor}; 
Rmerge (point group, 4m2) for 3386 reflections with 
exactly two observations= 0·042; all reflections used 
Table 1. Final refined parameters (x, y, z and 
Ueq x 104) 
Ucq = (113)2:;2:iU;ia;*a/a;.ai. 
x y z Ucq (A2) 
Au 652 (·3) 5652 2500 439 (1) 
Pl 1058 (1) 5593 (1) 717 (1) 481 (4) 
Cl 458 (4) 4959 (5) -262 (5) 681 (20) 
ClO 2116 (6) 5166 (6) 635 (8) 533 (24) 
Cll 2128 (7) 4273 (5) 1132 (7) 810 (27) 
Cl2 3017 (9) 3932 (6) 1106 (9) 1030 (35) 
Cl3 3626 (7) 4503 (8) 1673 (9) 1052 (35) 
Cl4 3624 (6) 5342 (8) 1209 (9) 951 (33) 
Cl5 2746 (5) 5736 (6) 1198 (8) 768 (26) 
C20 1107 (5) 6670 (5) 219(6) 597 (20) 
C21 300 (9) 7167 (7) 439 (10) 894 (37) 
C22 407 (6) 8091 (6) 119 (9) 1006 (34) 
C23 697 (8) 8193 (6) -994 (9) 1077 (36) 
C24 1465 (9) 7702 (8) -1196(11) 1442 (48) 
C25 1372 (6) 6772 (6) -934 (7) 907 (27) 
P2 3292 (3) 8292 2500 899 (8) 
Fl 3128 (8) 8509 (8) 1366 (5) 2497 (54) 
F2 3924 (9) 8924 2500 3533 (72) 
F3 2639 (8) 7639 2500 2385 (44) 
F4 3854 (8) 7670 2050 (8) 2838 (63) 
Table 2. Selected distances (A) and angles (0 ) 
Au-Au 
Au-Pl 
Pl-Cl 
Pl-Au-Pl 
Au-Pl-Cl 
Au-Pl-ClO 
Au-Pl-C20 
ClO-Pl---Cl 
C20-P 1---C 1 
2-935 (1) 
2·314 (2) 
l ·848 (7) 
160·6 (1) 
120·7 (2) 
109· l (3) 
107-4 (2) 
103-8 (4) 
108·2 (3) 
Pl-ClO 
Pl-C20 
Cl-Cl 
C20-Pl-CIO 
Cl-Cl-Pl 
Cll-ClO-Pl 
ClS-ClO-Pl 
C21-C20-Pl 
C25---C20-Pl 
1·819 (10) 
l ·825 (8) 
1·463 (9) 
107·0 (4) 
117·8 (5) 
109·4 (6) 
111·2 (6) 
112·8 (6) 
115·9 (6) 
in solution and refinement of the structure. Au-atom 
coordinates found from Patterson map, remainder of 
structure by successive. structure factor-Fourier cal-
culations; full-matrix least-squares refinement using 
F2 values. H atoms placed by calculation 0·95 A 
from their C atoms, with isotropic B's of 10·0 A2, 
H-atom coordinates not refined but adjusted once 
near conclusion of refinement; 165 parameters 
refined, including scale factor, all refinable coordi-
nates of non-H atoms and their anisotropic U;/s. w 
= l/u2(Fa2), final R 0·064 (wR on F 2 = 0.005) for 
3525 reflections with F0 2 > 0, 0·038 (wR on F 2 = 
0.004) for 2440 reflections with F/ > 3u(F0 2), final 
goodness of fit, S = l ·46. The absolute configuration 
for the structure which we describe here was con-
firmed by refining both alternatives; the incorrect one 
gives R = 0·087 compared to R = 0·064 for the cor-
rect one. Variances [u2(Fa2)] derived from counting 
statistics plus an additional term, (0·0141)2, variances 
of the merged data by propagation of error plus 
another additional term, (0·0147)2; ratio of maximum 
shift to e.s.d. in final least-squares cycle, 0·07 for 
cation, O· 36 for F atoms of PF6 - anion; one peak 
2·7 e A- 3 between the two Au atoms, another 
1 ·8 e A - 3, O· 3 A from Au atom, all other peaks less 
W. P. SCHAEFER, R. E. MARSH, T. M. McCLESKEY AND H. B. GRAY 2555 
than 11 ·51 e A - 3, most negative peaks in vicinity of 
PF6 - ion. Atomic scattering factors and dispersion 
corrections taken from Cromer & Waber (1974). 
Programs used were those in CRYM (Duchamp, 
1964) and ORTEP (Johnson, 1976). Final param-
eters are given in Table I* and selected distances and 
angles in Table 2. 
A few words about absorption, which we expected 
might be a problem (µr max= l ·2). While the crystal 
* Tables of anisotropic displacement parameters, complete dis-
tances and angles, observed and calculated structure factors and 
assigned H-atom parameters have been deposited with the British 
Library Document Supply Centre as Supplementary Publication 
No. SUP 54393 (22 pp.). Copies may be obtained through The 
Technical Editor, International Union of Crystallography, 5 
Abbey Square, Chester CH 1 2HU, England. 
C25 . . ~YJ 
C2J ~f.24 
Fig. I. An ORTEP (Johnson, 1976) view of the cation with 50% 
probability ellipsoids showing the numbering system. H atoms 
are not shown. 
Fig. 2. An ORTEP (Johnson, 1976) drawing of four cations and 
four anions viewed perpendicular to the ab plane. The unit cell 
is outlined; atoms are shown at the 50% probability level with 
H atoms omitted. 
was not far from cube-shaped, its morphology did 
not match its point group, and some of the bounding 
faces appeared to be complicated; a few were hidden 
in the cement. Our attempts to apply absorption 
corrections on the basis of our measurements of the 
crystal faces, or on the basis of l/f-scan measure-
ments, were unsuccessful, in that they led to some-
what larger values of the goodness-of-fit for merging 
(the range of calculated transmission coefficients was 
0·25-0· 37 and the relative transmissions for three 
reflections used for the l/f scans were 0·85-1·l0). We 
believe that the excellent GOF we obtained for aver-
aging the two uncorrected data sets - l ·08 - suggests 
that absorption was not a serious problem, but we 
caution that our final U u values may include some 
absorption effects. 
Discussion. The cation in this compound is posi-
tioned at a point of 222 symmetry; thus one quarter 
of the cation is the asymmetric unit. An ORTEP 
drawing of the cation showing the numbering system 
is given in Fig. 1. Fig. 2 is a view perpendicular to 
the ab plane. The two Au atoms are 2·935 (1) A 
apart, 0·05 A farther than in Au (metal) but indica-
tive of a substantial Au-Au interaction. Fig. 1 shows 
the cation with the Au atoms apparently pulled 
toward each other by this bonding. The average 
length of Au-Au bonds in 123 dimers listed in the 
Cambridge Structural Database (Orpen, Brammer, 
Allen, Kennard, Watson & Taylor, 1989) is 2·87 A, 
with actual distances ranging from 2·55 to 3·29 A. 
Thus the distance observed here is slightly longer 
than average and within normal limits. The Au-P 
distance is 2·314 (2) A, somewhat shorter than the 
value of 2·400 (13) A given for eight compounds of 
1,2-bis( diphenylphosphino )ethane with gold (Orpen 
et al., 1989), the closest match to the ligand used in 
this work. Other bond distances and angles are 
normal. The PF6 - anion packs near the Au-Au 
group but at van der Waals distances or further 
away. The F atoms of this ion have large (apparent) 
thermal motions, reaching 0·8 A r.m.s. deviation for 
F2. A model with disordered F atoms might have 
been used, but we considered it unlikely to improve 
the overall results significantly. 
This work was supported in part by National 
Science Foundation Grant CHE 89-22067. 
References 
CHE, C. M., WONG, W. T., LAI, T. F. & KWONG, H. L. (1989). J. 
Chem. Soc. Chem. Commun. 4, 243-244. 
CROMER, D. T. & WABER, J. T. (1974). International Tables for 
X-ray Crystallography, Vol. IV, pp. 71 and 148. Birmingham: 
Kynoch Press. (Present distributor Kluwer Academic 
Publishers, Dordrecht.) 
2556 
DUCHAMP, D. J. (1964). CRYM crystallographic computing 
system. Am. Crystallogr. Assoc. Meet., Bozeman, Montana. 
Paper Bl4, p. 29. 
JOHNSON, C. K. (1976). ORTEPII. Report ORNL-5138. Oak 
Ridge National Laboratory, Tennessee, USA. 
KHAN, N. I., FACKLER, J.P. JR, KING, c., WANG, J. c. & WANG, 
S. (1989). Inorg. Chem. 27, 1672-1673. 
Acta Cryst. (1991). C47, 2556-2558 
KING, C., WANG, J.C., KHAN, N. I. & FACKLER, J.P. JR (1989). 
Inorg. Chem. 28, 2145-2149. 
ORPEN, A. G., BRAMMER, L., ALLEN, F. H., KENNARD, 0., 
WATSON, D. G. & TAYLOR, R. (1989). J. Chem. Soc. Dalton 
Trans. pp. Sl-S83. 
USON, R., LAGUNA, A. & VICENTE, J. (1977). J. Organomet. Chem. 
131, 471-475. 
Structure of P-Mo2(SCN)4[(2S,3S)-2,3-bis( diphenylphosphino )butaneh Nitromethane 
So Iv ate 
BY A. A. AITCHISON, L. J. FARRUGIA* AND R. D. PEACOCK 
Department of Chemistry, University of Glasgow, Glasgow G12 8QQ, Scotland 
(Received 26 April 1991; accepted 4 July 1991) 
Abstract. Bis-µ-[(2S,3S)-2,3-bis( diphenylphosphino )-
butane-P,P']-bis[bis(thiocyanato )molybdenum ](Mo-
Mo) nitromethane solvate, [Mo2(SCN)iC28H28-
P2)2].CH3N02, Mr= 1338.2, orthorhombic, P21212, a 
= 15.890 (3), b = 17 .532 (3), c = 24. 745 (3) A, v = 
6893 (2) A3, Z = 4, Dx = 1.29 g cm- 3, A(Mo Ka)= 
0.71069 A,µ= 6.0 cm- 1, F(OOO) = 2736, T= 298 K, 
R = 0.067 for 3341 unique observed reflections. The 
asymmetric unit consists of two half molecules of the 
title complex, each residing on a twofold axis. The 
Mo-Mo quadruple bond [2.172 (3) and 2.154 (3) A] 
is bridged by an S,S-dppb ligand, and each Mo atom 
is N-coordinated to two thiocyanate groups. The 
intraligand P-Mo-Mo-P torsion angles (<p) are 
25.8 (3) and 21.9 (3) 0 • 
Introduction. Compounds of the structural type 
,B-Mo2X4(PP)2 have been intensively studied in the 
recent past (Agaskar, Cotton, Fraser, Manojlovic-
Muir, Muir & Peacock, 1986). When the Mo2X4P 4 
core is twisted about the Mo-Mo axis, an 
inherently dissymmetric Moi+ chromophore results 
(Peacock, 1987). In order to observe the optical 
activity of this chromophore, it is necessary to stabi-
lize one conformer of the Mo2P2C2 ring by using a 
chiral diphosphine such as (2S,3S)-2,3-bis(diphenyl-
phosphino )butane, (S,S-dppb ). One of us has 
previously reported the structures of ,B-Mo2X4(S,S-
dppb) (X = Cl, Br) (Agaskar et al., 1986), and herein 
we detail the structure of the thiocyanate derivative. 
Experimental. The title complex was synthesized as 
follows. (NH4)4[Mo2(SCN)8].6H20 (0.08 g) and a 
* Author to whom correspondence should be addressed. 
0108-2701/91/122556-03$03.00 
slight excess of S,S-dppb (0.09 g) were refluxed in 
methanol (35 ml) under nitrogen atmosphere. The 
colour of the solution changed from green to yellow-
brown during the course of the reaction. Removal of 
the methanol, followed by chromatography on 
alumina, using toluene as an eluant afforded a yellow 
band. The product was recrystallized from nitro-
methane. Analysis, calculated for C60H56Mo2N4P 484: 
C 56.4, H 4.42, N 4.39%; found C 56.00, H 4.37, N 
4.41 % . A yellow-green prism, ca 0.5 x 0.4 x 
0.15 mm, was mounted in a general position on a 
glass fibre; systematic absences: h = 2n + 1 in hOO, k 
= 2n + 1 in OkO; the reflections l = 2n + 1 in 001 were 
systematically weak; Enraf-Nonius CAD-4F diffrac-
tometer; graphite monochromator; ()/2() scan mode; 
cell parameters refined by least-squares methods on 
basis of 25 independent (} values, 11 < (} < 13°; inten-
sities measured to (} = 25.0° over hkl range 0 to 18, 0 
to 20, 0 to 29; 402 and 042 measured every 2 hand 
showed a decay of ca 3 % over data collection; 6990 
data measured, 6935 independent data with 3341 
having I> 2.0u(l) considered observed and used in 
structure determination and refinement: Rint = 0.034; 
corrected for decomposition, Lorentz-polarization 
effects and absorption (D/FABS; Walker & Stuart, 
1983), max. and min. values of applied absorption 
correction 1.40 and 0. 77; solved by direct methods 
(MITHRIL; Gilmore, 1984) for heavy atoms, and 
subsequent full-matrix least squares; anisotropic 
thermal parameters for all non-H atoms except aryl 
C atoms and solvent atoms; phenyl groups refined as 
rigid groups with idealized geometry, C-C 1.395, 
C-H 1.0 A; aliphatic C-H H atoms included at 
calculated positions, C-H 1.0 A, fixed contributions 
to structure factors for all H atoms, with U = 
© 1991 International Union of Crystallography· 


A luminescent gold complex: bis-μ-[bis(dicyclohexylphosphino)ethane-P,P']-digold bis(hexafluorophosphate)

http://authors.library.caltech.edu/70327/1/hh0520.pdf

A luminescent gold complex: bis-μ-[bis(dicyclohexylphosphino)ethane-P,P']-digold bis(hexafluorophosphate)

Abstract

Similar works

Full text

Available Versions

Caltech Authors - Main