Pseudopolymorphism in nickel(II) complexes with 6-bromopicolinic acid. Synthesis, structural and thermal studies

Article abstract of DOI:10.1016/j.molstruc.2009.05.002

Nickel(II) complexes of 6-bromopicolinic acid, namely [Ni(6-Brpic)₂(H₂O)₂]·3H₂O (1) and [Ni(6-Brpic)₂(H₂O)₂]·H₂O (2) were prepared and characterized by spectroscopic m

Full text of DOI:10.1016/j.molstruc.2009.05.002

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Journal of Molecular Structure 930 (2009) 121–125
Contents lists available at ScienceDirect
Journal of Molecular Structure
journal homepage: www.elsevier.com/locate/molstruc
Pseudopolymorphism in nickel(II) complexes with 6-bromopicolinic acid.
Synthesis, structural and thermal studies
*
´
Boris-Marko Kukovec, Zora Popovic
Laboratory of General and Inorganic Chemistry, Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, HR-10000 Zagreb, Croatia
a r t i c l e i n f o
a b s t r a c t
Article history:
Nickel(II) complexes of 6-bromopicolinic acid, namely [Ni(6-Brpic)2(H2O)2]Á3H2O (1) and [Ni(6-Brpic)2
(H2O)2]ÁH2O (2) were prepared and characterized by spectroscopic methods (IR), their molecular and
crystal structures were determined by X-ray crystal structure analysis and their thermal stability by
TGA/DTA methods. Compound 1 was prepared by reaction of nickel(II) nitrate and 6-bromopicolinic acid
in aqueous solution at pH value of 8, while 2 was obtained by spontaneous recrystallization of 1 in its
mother liquor during few months. These complexes are an example of pseudopolymorphs which differ
in number of co-crystallized water molecules but both crystallize in the same crystal system (triclinic).
X-ray structural analysis revealed octahedron as a coordination polyhedron in both 1 and 2 and the same
N,O-chelated coordination mode of 6-bromopicolinic acid. The coordination sphere of nickel(II) ion is
completed by two coordinated water molecules. These pseudopolymorphs differ in their crystal struc-
Received 24 March 2009
Received in revised form 28 April 2009
Accepted 1 May 2009
Available online 9 May 2009
Keywords:
Nickel(II) complexes
6-Bromopicolinic acid
p–p Interactions
Pseudopolymorphism
tures which are dominated by intermolecular O–HÁ Á ÁO hydrogen bonds and
p–p stacking interactions
TGA/DTA methods
in both cases. The infrared spectra of 1 and 2 are very similar so these pseudopolymorphs cannot be
unambiguously distinguished by IR spectroscopy. Thermal methods confirm number of co-crystallized
water molecules in both pseudopolymorphs.
Ó 2009 Elsevier B.V. All rights reserved.
1. Introduction
hydration. The possibility of formation of pseudopolymorphs should
be considered in the presence of solvent. Although transformation of
Polymorphism and crystal growth are among the most inten-
sively researched area of present times because of the tremendous
basic and commercial interest in pharmaceutical solids and new
materials. The primary process of crystallization, governed pre-
dominantly by intermolecular interactions, remains intractable
even for small organic molecules due to the complexity with which
molecules interact with each other [1,2].
Moreover, conversions between different polymorphs i.e. crys-
tal forms are possible and often take place. Among many possibil-
ities for conversion depending on variables like temperature or
pressure, there are several more specific ones such as a conversion
of metastable form into a thermodynamically more stable one
through very slow kinetics, conversion of unsolvated form into var-
ious solvates or co-crystalline forms, conversion of anhydrous form
into hydrates or a conversion of solvate into another one with dif-
ferent degree of solvation etc.
1 into 2 on prolonged standing of reaction mixture is not surprising,
it could not be anticipated.
As a part of our wider research programme on polymorphism or
isomerism of the late 3d-metal complexes with picolinic acid and
its derivatives [3–7] we undertook this research, partially because
of a lack of data in coordination chemistry of the transition metals
and 6-bromopicolinic acid as a ligand. Until now, only ruthe-
nium(II) [8] and copper(II) [6] complexes with 6-bromopicolinic
acid have been prepared and structurally characterized.
2. Experimental
2.1. Materials and physical measurements
All chemicals for the syntheses were used as received without
further purification. Nickel(II) nitrate hexahydrate was purchased
from Kemika, Croatia, while 6-bromopicolinic acid was purchased
from Aldrich.
In this paper, we report two pseudopolymorphs of nickel(II) com-
plex with 6-bromopicolinic acid, namely [Ni(6-Brpic)2(H2O)2]Á3H2O
(1) and [Ni(6-Brpic)2(H2O)2]ÁH2O (2) as an example of transforma-
tion of one crystal form into another with different degree of
CHN analyses were performed on Perkin–Elmer 2400 Series II
CHNS analyzer in the Analytical Services Laboratories of the Ruder
´
Boškovic Institute, Zagreb, Croatia.
The IR spectra were obtained from KBr pellets in the range 4000–
* Corresponding author. Tel.: +385 1 4606354; fax: +385 1 4606341.
E-mail address: zpopovic@chem.pmf.hr (Z. Popovic
´).
450 cmÀ1 with a Perkin–Elmer Spectrum RXI FTIR-spectrometer.
0022-2860/$ - see front matter Ó 2009 Elsevier B.V. All rights reserved.
doi:10.1016/j.molstruc.2009.05.002

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122
B.-M. Kukovec, Z. Popovic / Journal of Molecular Structure 930 (2009) 121–125
Table 1
TGA/DTA measurements were performed at heating rate of
10 °C minÀ1 in the temperature range of 25–600 °C, under nitrogen
flow of 10 mL minÀ1 on instrument Mettler-Toledo TGA/SDTA
851e. Approximately 10 mg of sample were placed in standard alu-
Crystal data and details of the structure determination for [Ni(6-Brpic)2(H2O)2]Á3H2O
(1) and [Ni(6-Brpic)2(H2O)2]ÁH2O (2).
Compound
1
2
minium crucible (40 lL).
Formula
Mr
C12H6NiBr2N2O9
540.68
C12H12NiBr2N2O7
514.73
Colour and habit
Crystal system, space group
Crystal dimensions (mm3)
Unit cell parameters:
a (Å)
Green, prism
Triclinic, P1
0.80 Â 0.18 Â 0.16
Green, block
Triclinic, P1
0.59 Â 0.48 Â 0.32
2.2. cis-diaquabis(6-bromopyridine-2-carboxylato-N,O)nickel(II)
trihydrate, [Ni(6-Brpic)2(H2O)2]Á3H2O, (1)
ꢀ
ꢀ
A solution of 6-bromopicolinic acid (0.05 g, 0.25 mmol) in
10 mL of water was added to a solution of nickel(II) nitrate hexahy-
drate (0.04 g, 0.14 mmol) in 5 mL of water. The pH value of the
resulting green solution was adjusted to 8 by adding a few drops
of concentrated ammonia solution and then left to stand at room
temperature for 3 weeks. The light green crystals were obtained
and filtered off, washed with small portion of water and dried in
vacuum. Yield: 0.04 g (50%). Anal. Calcd. for C12H16NiBr2N2O9
(550.79): C, 26.17; H, 2.93; N, 5.09%. Found: C, 26.21; H, 3.11; N
5.19%. IR data (KBr pellet, cmÀ1): 3344(m), 1643(s), 1586(s),
1555(s), 1441(m), 1404(m), 1377(s), 1248(w), 1159(w), 1128(m),
1083(w), 1003(w), 766(m), 746(m).
8.9359(3)
13.8752(9)
16.1480(11)
72.401(6)
78.756(4)
80.779(4)
1860.79(19)
0.71073
8.0378(2)
11.2015(3)
19.8394(5)
74.148(2)
79.170(2)
71.703(3)
1621.21(8)
0.71073
b (Å)
c (Å)
a
(°)
b (°)
c
(°)
V (Å3)
Radiation, MoKa (Å)
Z
4
4
Dcalc(g cmÀ3
)
1.966
5.385
2.109
6.164
l
(mmÀ1
)
h range for data collection (°)
h, k, l range
3.88–25.00
À10:10; À16:16,
À19:19
3.93–27.00
À10:10; À14:14,
À25:25
Scan type
x
x
No. measured reflections
No. independent reflections (Rint
33140
6517 (0.2339)
4754
35760
7028 (0.0424)
5043
2.3. cis-diaquabis(6-bromopyridine-2-carboxylato-N,O)nickel(II)
monohydrate, [Ni(6-Brpic)2(H2O)2]ÁH2O, (2)
)
No. observed reflections, I ꢀ2
r(I)
No. refined parameters
488
470
Ra, wRb [I ꢀ 2
r
(I)]
0.0683, 0.1293
0.1138, 0.1444
0.0535, 0.1738
1.112
0.0398, 0.1029
0.0638, 0.1089
0.0669, 0
1.048
A solution of 6-bromopicolinic acid (0.10 g, 0.50 mmol) in
15 mL of water was added to a solution of nickel(II) nitrate hexahy-
drate (0.07 g, 0.24 mmol) in 5 mL of water. The pH value of the
resulting green solution was adjusted to 8 by adding a few drops
of concentrated ammonia solution. The solution was left to stand
at room temperature for 1 week and then the light green crystals
of 1 were formed. The crystals of 1 were left to stand in mother li-
quor at room temperature for 2 months, resulting with the forma-
tion of dark green crystals of 2. These crystals were filtered off,
washed with small portion of water and dried in vacuum. Yield:
0.10 g (83%). Anal. Calcd. for C12H12NiBr2N2O7 (514.75): C, 28.00;
H, 2.35; N, 5.44%. Found: C, 28.14; H, 2.41; N 5.46%. IR data (KBr
pellet, cmÀ1): 3400(m), 1641(s), 1584(s), 1554(s), 1441(m),
1375(s), 1248(w), 1161(m), 1127(m), 1085(w), 1004(w), 779(m),
771(m), 742(m).
R, wR [all data]
g1, g2 in wc
Goodness of fit on F2, Sd
Max., min. electron density (e ÅÀ3
)
1.677, À1.125
1.398, À1.090
Maximum
D/r
0.001
0.001
Range of transmission factors min., 0.330, 0.420
max.
Extinction coefficient
0.035, 0.135
–
0.0125(6)
P
P
a
b
c
R = ||Fo| À |Fc||/ |Fo|.
P
P
wR = [ (Fo À Fc2)2/ w(Fo2)2]1/2
.
2
w = 1/[
r
2(Fo2) + (g1P)2 + g2P] where P = (Fo2 + 2Fc2)/3.
P
S = [w(Fo À Fc2)2/(Nobs À Nparam)]1/2
.
d
2
using SHELXL-97 DFIX instruction. The isotropic Uiso(H) value
was fixed at the same time [Uiso(H) = 1.2Ueq(O)].
Calculations were performed with SHELXS-97 [10], SHELXL-97
[10] and PLATON [11]. The molecular graphics were done with OR-
TEP-3 [12] and MERCURY (Version 1.4.2) [13].
2.4. X-ray single crystal structure determination
Crystal data and details of the structure determination for 1 and
2 are given in Table 1.
Suitable single crystals of 1 and 2 were selected and mounted in
air onto thin glass fibres. The data collection was carried out on
Oxford Diffraction Xcalibur four-circle kappa geometry diffractome-
ter with Xcalibur Sapphire 3 CCD detector by applying the CrysAlis
Software system, Version 171.32.24 at room temperature (296 K)
[9]. Data reduction has been applied by the same programme [9].
The X-ray diffraction data have been corrected for Lorentz-
polarization factor and scaled for absorption effects by multi-scan.
The structures were solved by direct methods. Refinement proce-
dure by full-matrix least squares methods based on F2 values
against all reflections has been performed including anisotropic
displacement parameters for all non-H atoms.
3. Results and discussion
3.1. Preparation of complexes
Complex [Ni(6-Brpic)2(H2O)2]Á3H2O (1) was prepared by reac-
tion of nickel(II) nitrate hexahydrate and 6-bromopicolinic acid
in aqueous solution in the presence of ammonia, at a pH value of
at least 8. Complex 1 cannot be prepared in acidic aqueous solu-
tions (without the addition of base e.g. ammonia).
Pseudopolymorph [Ni(6-Brpic)2(H2O)2]ÁH2O (2) was obtained by
spontaneous recrystallization of 1 in its mother liquor during
2 months. Two crystal water molecules are lost during this process,
leading to the formation of another pseudopolymorph, which
crystallizesina samecrystalsystemwithdifferentnumberofco-crys-
tallized water molecules (vide infra). Compound 1 appears as light
green prisms, it is not air-stable and decomposes in air due to the
release of co-crystallized water molecules. Compound 2 is air-stable
and appears as dark green blocks. Both compounds are soluble in
water, ethanol and in solvents with donor properties (N,N-dimethyl-
formamide, dimethylsulfoxide, pyridine and 4-picoline).
The positions of hydrogen atoms belonging to the carbon atoms
Csp2 were geometrically optimized applying the riding model
[Csp2–H, 0.93 Å; Uiso(H) = 1.2Ueq(C) for Csp2]. Hydrogen atoms
belonging to water molecules in 1 could not be found in difference
Fourier maps, probably due to the lower quality of the crystal and
the data collected. However, crystals of better quality could not be
prepared in spite of all our attempts. Atoms O16 and O17 from co-
crystallized water molecules in 1 are disordered. Hydrogen atoms
belonging to water molecules in 2 were found in difference Fourier
maps, the distance between them and the corresponding water
oxygen atoms was restrained to the average value of 0.82(3) Å

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B.-M. Kukovec, Z. Popovic / Journal of Molecular Structure 930 (2009) 121–125
106.3(2)° for one crystallographically independent molecule in 1
and 79.5(2)–107.2(2)° for the other. The values of trans pairs of do-
nor atoms are in the range of 163.0(1)–166.9(1)° for one crystallo-
graphically independent molecule in 2 and 160.0(1)–168.4(1)° for
the other. The values of cis pairs of donor atoms are in the range
of 79.1(1)–112.0(1)° for one crystallographically independent mol-
ecule in 2 and 78.6(1)–111.2(1)° for the other. These values indi-
cate large distortion from the ideal octahedral geometry. The
distortion is also observed in the bite angles O1–Ni1–N1 with val-
ues of 79.5(2)° for 1 and 79.1(1)° for 2, O3–Ni1–N2 with values of
79.8(2)° for 1 and 80.9(1)° for 2, O7–Ni2–N3 with values of 79.5(2)°
for 1 and 78.6(1)° for 2 and O9–Ni2–N4 with values of 79.7(2)° for
1 and 79.6(1)° for 2. The bite angles are rather small due to the che-
late ring formation (Table 2).
The crystal packing of 1 is dominated by numerous hydrogen
bonds of the O–HÁ Á ÁO type (Fig. 2a). The hydrogen atoms which
belong to coordinated and co-crystallized water molecules could
not be found in difference Fourier maps. Therefore, the intermolec-
ular OÁ Á ÁO contacts shorter than 3 Å are the indication of the pres-
ent hydrogen bonds. Two molecules of nickel(II) complex are
linked into centrosymmetric dimers which are further connected
into an infinite chain in [1 0 0] direction by hydrogen bonds. Such
chains are assembled into 3D structure by
p–p stacking interac-
tions [16–20] between pyridine rings defined by atoms N3/C13/
C14/C15/C16/C17 and N3i/C13i/C14i/C15i/C16i/C17i [symmetry
code (i): 1 À x, 1 À y, 1 À z; centroid-centroid distance 3.747(4) Å;
the angle between the planes 0°; the perpendicular distance
Fig. 1. ORTEP-3 drawing of [Ni(6-Brpic)2(H2O)2]ÁH2O (2) with the atomic number-
ing scheme. Only one crystallographically independent molecule of complex is
shown, while the co-crystallized water molecules are omitted. The thermal
ellipsoids are drawn at the 50% probability level at 296 K.
between the planes 3.308(3) Å; the slippage 1.760 Å] and by
p–p
stacking interactions between pyridine rings defined by atoms
N4/C19/C20/C21/C22/C23 and N4ii/C19ii/C20ii/C21ii/C22ii/C23ii
[symmetry code (ii): 1 À x, 1 À y, Àz; centroid–centroid distance
3.618(4) Å; the angle between the planes 0°; the perpendicular dis-
tance between the planes 3.270(3) Å; the slippage 1.548 Å]. Such
crystal packing results with the formation of hydrophobic and
hydrophilic areas in the structure. Hydrophobic areas are domi-
3.2. Crystal structures of 1 and 2
There are two crystallographically independent molecules of
complex in the asymmetric unit of compounds 1 and 2. The asym-
metric unit of 1 and 2 also contains six and two co-crystallized
water molecules, respectively. ORTEP-3 view of the molecular
structure of compound 2 is depicted in Fig. 1, while molecular
structure of compound 1 is not shown due to the great similarity
with the structure of 2. The crystal structures of compounds 1
and 2 are shown in Fig. 2a and 2b, respectively. Some selected
interatomic bond distances and angles are listed in Table 2, as well
as hydrogen bond geometry for 2 in Table 3.
The nickel(II) ion in the molecular structures of 1 and 2 exhibits
a distorted octahedral coordination geometry. It is coordinated by
two water molecules and two N,O-bidentate 6-bromopicolinate li-
gands, which form five-membered chelate rings in both 1 and 2.
These ligands are approximately perpendicular to each other,
while two water molecules in cis position complete the coordina-
tion sphere of nickel(II) ion (Fig. 1). The angles between them have
the values of 93.6(2)° for one crystallographically independent
molecule in 1 (angle O6–Ni1–O5) and of 93.8(2)° for the other crys-
tallographically independent molecule in 1 (angle O11–Ni2–O12).
The analogous values for 2 are 88.4(1)° for angle O6–Ni1–O5 and
89.7(1)° for angle O11–Ni2–O12. The bond distances and angles
in 1 and 2 are quite similar, as expected for pseudopolymorphs (Ta-
ble 2). The bond distances Ni–N and Ni–O (N and O atoms are from
6-bromopicolinic acid) in 1 and 2 are in accordance with the values
from the literature i.e. for trans-diaquabis(pyridine-2-carboxylato-
N,O)nickel(II) dihydrate [14], trans-bis(pyridine-2-carboxylato-
N,O)bis(urea-O)nickel(II) urea disolvate monohydrate [15] and for
pseudopolymorphs of cis-diaquabis(6-methylpyridine-2-carboxy-
lato-N,O)nickel(II) [5].
nated by
p–p stacking interactions, while hydrophilic ones are
dominated by O–HÁ Á ÁO hydrogen bonds between co-crystallized
water molecules (Fig. 2a).
The crystal packing of 2 is also dominated by numerous hydro-
gen bonds of the O–HÁ Á ÁO type (Fig. 2b). The oxygen atoms from
coordinated and co-crystallized water molecules participate in
hydrogen bonds as proton donors, while carboxylate oxygen atoms
(including water molecule atoms O6, O12, O13 and O14) act as
proton acceptors (Table 3). Two molecules of nickel(II) complex
are linked into centrosymmetric dimers which are further
connected into an infinite chain in [1 0 0] direction by hydrogen
bonds. Such chains are assembled through co-crystallized water
molecules in [0 1 0] direction, forming a network in ab plane. These
networks are further connected in [0 0 1] direction by p–p stacking
interactions [16–20] between pyridine rings defined by atoms N1/
C1/C2/C3/C4/C5 i N1i/C1i/C2i/C3i/C4i/C5i [symmetry code (i): Àx,
1 À y, Àz; centroid-centroid distance 3.349(2) Å; the angle
between the planes 0°; the perpendicular distance between the
planes 3.194(2) Å; the slippage 1.007 Å], forming a 3D structure
(Fig. 2b). There is one more p–p stacking interaction between pyr-
idine rings defined by atoms N3/C13/C14/C15/C16/C17 i N3ii/C13ii/
C14ii/C15ii/C16ii/C17ii [symmetry code (ii): 1 À x, Ày, 1 À z;
centroid–centroid distance 3.526(2) Å; the angle between the
planes 0°; the perpendicular distance between the planes
3.290(2) Å; the slippage 1.267 Å].
3.3. Vibrational spectroscopy
The bond angles around Ni involving trans pairs of donor atoms
are in the range of 165.5(2)–172.7(2)° for one crystallographically
independent molecule in 1 and 165.6(2)–172.0(2)° for the other,
while for the cis pairs of donor atoms this range is 79.5(2)–
Infrared spectroscopy data confirm the coordination of 6-Brpic
ligand to nickel(II) ion via the carboxylate group in pseud-
opolymorphs 1 and 2, respectively. In the spectrum of 1 and 2

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B.-M. Kukovec, Z. Popovic / Journal of Molecular Structure 930 (2009) 121–125
124
Fig. 2. (a) A view (in bc plane) of crystal packing of [Ni(6-Brpic)2(H2O)2]Á3H2O (1), showing the intermolecular OÁ Á ÁO contacts. (b) A view (in bc plane) of crystal packing of
[Ni(6-Brpic)2(H2O)2]ÁH2O (2), showing centrosymmetric dimers linked with water molecules into a chain in [0 1 0] direction by hydrogen bonds of the O–HÁ Á ÁO type
represented by thin lines. These chains are further mutually connected by p–p interactions in [0 0 1] direction.
Table 2
Selected bond distances (Å) and angles (°) for [Ni(6-Brpic)2(H2O)2]Á3H2O (1) and [Ni(6-Brpic)2(H2O)2]ÁH2O (2).
1
2
Bond distances
Ni1–O1
Ni1–O3
Ni1–O5
Ni1–O6
2.008(4)
2.014(4)
2.072(5)
2.050(5)
2.168(5)
2.161(5)
Ni2–O7
Ni2–O9
Ni2–O11
Ni2–O12
Ni2–N3
Ni2–N4
1.999(4)
2.012(5)
2.066(5)
2.088(4)
2.162(5)
2.158(6)
Ni1–O1
Ni1–O3
Ni1–O5
Ni1–O6
Ni1–N1
Ni1–N2
2.022(3)
1.991(3)
2.091(3)
2.062(3)
2.159(3)
2.097(3)
Ni2–O7
Ni2–O9
Ni2–O11
Ni2–O12
Ni2–N3
Ni2–N4
2.027(3)
2.024(3)
2.062(3)
2.095(3)
2.157(3)
2.135(3)
Ni1–N1
Ni1–N2
Bond angles
O1–Ni1–O3
O1–Ni1–O6
O3–Ni1–O6
O1–Ni1–O5
O3–Ni1–O5
O6–Ni1–O5
O1–Ni1–N2
O3–Ni1–N2
O6–Ni1–N2
O5–Ni1–N2
O1–Ni1–N1
O3–Ni1–N1
O6–Ni1–N1
O5–Ni1–N1
N2–Ni1–N1
172.7(2)
86.4(2)
88.0(2)
86.9(2)
88.7(2)
93.6(2)
105.0(2)
79.8(2)
91.5(2)
167.3(2)
79.5(2)
106.3(2)
165.5(2)
88.8(2)
89.2(2)
O7–Ni2–O9
O7–Ni2–O11
O9–Ni2–O11
O7–Ni2–O12
O9–Ni2–O12
O11–Ni2–O12
O7–Ni2–N4
O9–Ni2–N4
O11–Ni2–N4
O12–Ni2–N4
O7–Ni2–N3
O9–Ni2–N3
O11–Ni2–N3
O12–Ni2–N3
N4–Ni2–N3
172.0(2)
87.8(2)
88.3(2)
86.2(2)
87.1(2)
93.8(2)
104.7(2)
79.7(2)
167.1(2)
90.3(2)
79.5(2)
107.2(2)
86.8(2)
165.6(2)
92.3(2)
O1–Ni1–O3
O1–Ni1–O6
O3–Ni1–O6
O1–Ni1–O5
O3–Ni1–O5
O6–Ni1–O5
O1–Ni1–N2
O3–Ni1–N2
O6–Ni1–N2
O5–Ni1–N2
O1–Ni1–N1
O3–Ni1–N1
O6–Ni1–N1
O5–Ni1–N1
N2–Ni1–N1
166.9(1)
88.5(1)
90.2(1)
83.9(1)
83.0(1)
88.4(1)
112.0(1)
80.9(1)
86.4(1)
163.0(1)
79.1(1)
103.4(1)
165.9(1)
97.1(1)
91.9(1)
O7–Ni2–O9
O7–Ni2–O11
O9–Ni2–O11
O7–Ni2–O12
O9–Ni2–O12
O11–Ni2–O12
O7–Ni2–N4
O9–Ni2–N4
O11–Ni2–N4
O12–Ni2–N4
O7–Ni2–N3
O9–Ni2–N3
O11–Ni2–N3
O12–Ni2–N3
N4–Ni2–N3
168.4(1)
89.6(1)
84.4(1)
81.5(1)
88.4(1)
89.7(1)
107.1(1)
79.6(1)
163.1(1)
95.3(1)
78.6(1)
111.2(1)
88.3(1)
160.0(1)
92.3(1)