1485
L[ D[ Field et al[
w\ 791 w\ 672 w\ 628 m\ 587 vs\ 476 w\ 456 s\ 444 w\ ×09−5#[ All calculations were performed using the
430 vw\ 406 vw\ 353 w cm−0[ IR "CH1Cl1# ] n "CN# teXsan structure determination software package ð50Ł[
1045 m\ n "CO# 0859 vs cm−0
[
The structure was solved by direct methods ð57Ł and
extended with Fourier maps ð52Ł[ The re_nement
weighting scheme was based on counting statistics[
Generally the non!hydrogen atoms were re_ned aniso!
tropically\ and the hydrogen atoms were included in
the full matrix least squares re_nement at calculated
positions with group temperature factors[ The car!
bonyl and bromide ligands were found to be site dis!
ordered[ Although the carbonyl groups could be
located they could not be successfully re_ned ^ pos!
sibly because of orientation disorder or a consequence
of the site disorder[ Neutral atom scattering factors
were taken from Cromer and Waber ð53Ł[ Anomalous
dispersion e}ects were included in the structure factor
calculation ð54Ł\ and the values for Df ? and Df ý were
those of Creagh and McAuley ð55Ł[ The values for the
mass attenuation coe.cients are those of Creagh and
Hubbel ð56Ł[
Structure determinations
"a# ðOs"h4!C4Ph4#"CO#1BrŁ "0#[ Primitive orthor!
hombic cell constants were obtained from a least!
square re_nement against the setting angles of 14
re~ections in the range 05[07 ³ 1u ³ 13[97> measured
and re_ned on an Enraf!Nonius CAD!3 four!circle
di}ractometer\ employing graphite monochromated
MoÐKa radiation[ The intensities of three rep!
resentative re~ections measured every hour did not
change signi_cantly during the course of the data col!
lection[ An analytical absorption correction was
applied to the data and the data were also corrected
for Lorentz and polarisation e}ects[ All calculations
were performed using the teXsan ð50Ł crystallographic
software package[ The structure was solved in the
space group PBCA "è50# by direct methods ð51Ł and
expanded using Fourier techniques ð52Ł[ Non!hydro!
gen atom sites were modelled anisotropically and
hydrogen parameters were included in the full matrix
least squares re_nement with calculated positions and
group temperature factors[ Neutral atom scattering
factors were taken from Cromer and Waber ð53Ł[
Anomalous dispersion e}ects were included in the
structure factor calculation ð54Ł\ and the values for
Df ? and Dfý were those of Creagh and McAuley ð55Ł[
The values for the mass attenuation coe.cients are
those of Creagh and Hubbel ð56Ł[
Crystal data for ðOs"h4!C4Ph4#"CO#"P"OCH1#2
CCH2#BrŁ "5#
C30H23BrO3OsP\ M ꢁ 780[79\ monoclinic\ space
group\ P10:n "è03#\ a ꢁ 01[129"2#\ b ꢁ 05[024"8#\
c ꢁ 07[220"2# _\ b ꢁ 090[52"1#\ U ꢁ 2432"0# _2\
Dc"Z ꢁ 3# ꢁ 0[561 g cm−2\ F"999# ꢁ 0641\ m "Cu!
Ka# ꢁ 77[78 cm−0
[
Specimen ] yellow prism\
9[159×9[149×9[039 mm[ N ꢁ 4676\ Nunique ꢁ 4385\
No ꢁ 3131\ range of hkl 9 : 02\ 9 : 07\ −19 : 19\
Rmerge ꢁ 9[9216\ R ꢁ 9[955\ Rw ꢁ 9[962\ residual
extrema −1[64 and 1[20 e_2\ Tmin\max ꢁ 9[37\ 9[87[
Crystal data for ðOs"h4!C4Ph4#"CO#1BrŁ "0#
CONCLUSION
C26H14BrO1Os\ M ꢁ 660[60\ orthorhombic\ space
group\ PBCA "è50#\ a ꢁ 07[917"2#\ b ꢁ 03[810"1#\
c ꢁ 10[607"2# _\ U ꢁ 4731"0# _2\ Dc"Z ꢁ 7# ꢁ 0[65
The preparation and crystal structure of ðOs"h4!
C4Ph4#"CO#1BrŁ\ the _rst osmium complex of the pen!
taphenylcyclopentadienyl ligand\ has been described[
This completes the preparation and characterisation
of the iron!triad ðM"h4!C4Ph4#"CO#1BrŁ series of this
ligand[ The crystal structure of the osmium complex
is isostructural with those of its iron and ruthenium
analogues[ The osmium complex is stable in air and
readily undergoes monocarbonyl substitution with a
variety of ligands[ The crystal structure of one such
resultant complex\ ðOs"h4!C4Ph4#"CO#"P"OCH1#2
CCH2#BrŁ\ is also reported[
g cm−2\ F"999# ꢁ 1881\ m "MoÐKa# ꢁ 46[56 cm−0
[
Specimen ] yellow blade\ 9[414×9[014×9[901 mm[
N ꢁ 3051\ Nunique ꢁ 2865\ No ꢁ 1138\ range of hkl
9 : 04\ 9 : 07\ 9 : 11\ Rmerge ꢁ 9[055\ R ꢁ 9[939\
Rw ꢁ 9[932\ residual extrema −0[04 and 0[90 e_2\
Tmin\max ꢁ 9[16\ 9[75[
"b# ðOs"h4!C4Ph4#"CO#"P"OCH1#2CCH2#BrŁ "5#[
Lattice parameters at 10>C were obtained from a least
squares re_nement to the setting angles of 14 re~ec!
tions in the range 08[66 ³ 1u ³ 002[25>\ measured
and re_ned on a Rigaku AFC6R di}ractometer\
employing graphite monochromated CuKa radiation\
generated from a direct drive rotating anode[ Intensity
data were collected with v:1u scans to a maximum 1u
Acknowled`ements*We thank the Australian Research
Council for _nancial support and Dr M[ J[ Aroney for the
gift of P"OCH1#2CCH2[
value of 019[0>\ with
a
scan width of
"0[0¦9[24 tan u#>[ An empirical absorption correction
based on azimuthal scans of three re~ections was
applied to the data[ The data were corrected for Lor!
entz and polarisation e}ects and a small correction
for secondary extinction applied "coe.cient ꢁ 0[00
REFERENCES
0[ Bruce\ M[ I[\ Tomkins\ B[\ Wong\ F[ S[\ Skelton\
B[ W[ and White\ A[ H[\ J[ Chem[ Soc[\ Dalton
Trans[\ 0871\ 576[
Field
