Kansikas, Jarno

Kvick, Ake

Long, Yingcai

Mutikainen, Ilpo

Nelson, Mitchell

Revistes Catalanes amb Accés Obert

SYNCHROTRON X-RAY STRUCTURE OF A ZEOLITE
ZSM-39 ANALOGUE.
JARNO KANSIKAS', ILPO MUTIKAINEN'
University of Helsinki, Department of Chemistry , Vuorikatu 20, SF - 00100,
Helsinki , Finland,
YINGCAI LONG
University of Fudan , Shanghai , China,
MITCHELL NELSON-
Brookhaven National Laboratory , Upton , NY, 11973,
I4KE KVICA-
ESRF BP- 280, 38043 Grenoble Cedex , France.
INTRODUCTION
The nomenclature of zeolite framework structures is based on different
combinations oftetrhedrally coordinated T atom connections in aluminosilicates
or aluminophosphates. The framework is microporous consisting of closed
cavities in clathrasils, channels or their combinations. Clathrasils are a class of
compounds in which guest molecules are trapped within cavities formed by
crystalline lattice of different oxides, in the case of water such compounds are called
clathrate hydrates. In this case the cavities are formed by silica around a template
molecule. The structure of a high-silica zeolite ZSM-39 originally determined by
powder diffraction possesses a silica clathrate structure of 12-hedra and 16-hedra
formed by 5- and 6-rings of silicons (Figure 1) [1].
Crystal size of zeolites is generally small and many structural studies have
been carried out using powder diffraction [2]. According to the literature the
crystals prepared in systems with different template molecules have had dimensions
of 0.1 - 10 µm. The use of a quaternary 1-methyl-1,3,5,7-tetra-azaadamantane-
1-ium ion [(CH2)6N,+CHj]' [3] as a template has made it possible to obtain
crystals large enough (up to 0.07 mm) for single crystal data collection using
synchrotron radiation.
Work supported by the Academy of Finland and .* the Division of Chemical Sciences, U.S. Dept.
of Energy, under contract DE-AC02-76CH000 1 6.
[But II.Soc.Cat .Cien.],Vo!XIII, Num.1,1992
120 /. AI.AS/IA.I.S, 1. . 111'IIK :lI L:\', 11..ATLSOA, I. K\ ICh
Fig. I . The clathratc structure of7SM3t) showing the packing of I6-hedra which arc
tetrahedrally connected to each other through G-rings of T-atoms. The smaller cavities
are I 2-hedra formed by 5-rings.
Exi,F RIMFN'IAI.
The compound was synthesized hydrothermally in the system
[((.H,)(N4CH 3],O-Na,O-SiO,-AI,O 1-H )O. The silicon source was water glass
(P.Q. Corp) containing 26.98% SiO, and 8.4% Na,O. 'Ihe template molecule
1-methyl-1,3,5,7-tetraazaadamantane-l-iuIn iodide was provided by R.K.
McMullan. The gel formed was crystallized at 180" for 144 hours.
The crystal ofdimensions 0.07x0.07x0.07 mm was selected for data collection
on a Huber four circle diffractometer at the National Synchrotron Light Source
beam line X-7B. The space group from the powder work was determined to he
cubic Ed,3m (no. 227), as was also found in a single crystal determination ofZSM-
39 with methvlamine templates [4]. In order to confirm the space group, scans
were run along the reciprocal axes revealing several reflections systematically
absent in the cubic space group Fd3m. Based on systematic absences tetragonal
space group 14 /a (no. 88) was chosen. A total of2057 reflections with sinO/X< 1.0
A l (X=0.945 A, Ill)1 1) double crystal fixed exit monochromator) were collected
with w-scan methods resulting 859 unique reflections (I> 3(r(1)). Scan range was
0.1with thestepsizeof0.001". The scan time for each reflection was determined
gating (10,000 counts/step) the number of counts from the 1-detector.
The data was normalized using two test reflections measured at the intervals
of 25 reflections. An examle of a peak profile is shown in Figure 2.
1 Butl L SOC. Cat. CI C n. J,b'oI. X III, Nuni.1, 1992
SY.'SCIIROTRO.v X-RAYSTRCCI'URE OI :1 ZEOIIii 121
STD1 SM19
1.09521+04
1.2000E+01
1.9769E+0 1.9669E+01
Mavel 0.945 8 1.00 E 0.00 L 9.00
2Th 19 . 465 0n• 19.732 Chi -3. 446 Phi -114.204
Fig. 2. An example of the scan showing the FWHM of 0.008°.
RESULTS
Table 1. Crystal data
a 13.719(2) A 20-range 3 - 85°
b 13.719(2) A Scan-mode w
C 19.410(3) A Space group I41/a
V 3640.2(6) A3 Scan range 0.1°
µ 7.1 cm-1 Step size 0.0010
X 0.945 A Reflns
„
,d 2049
D 2.04 gcm-3 Reflns [,d 859
R 0.049 Nr. param. 133
Crystal
size
70x7Ox70 _m3
After the refinement of the cage atoms to the R-value of 5.7%, the difference
Fourier synthesis revealed several peaks in the cavities. The largest peak of
magnitude 4.5 eA-I was found in the center of the 16-hedron (point symmetry
[Bud ISoc.Cat.Clcn.],Vol.XII1,Num.1,1992
122 J. KANSIKAS, 1. MU17KAINEN, Y. LONG, h1. NELSON, A. KI'I(,'K
4 bar) surrounded by several smaller peaks. This residual electron density is
attributed to the disordered adamantanium ion. Based on the density
measurements, elementary analyses and difference Fourier electron densities,
refined occupancy factors of the water and the template molecule were found to
be 0.5 and 0.125, respectively (Figures 3 and 4).
313
SIS
03
01
Fig. 3. The asymmetric unit of theZSM39 framework with atomic labelling. White
circles show the connections to the symmetry related atoms.
Fig. 4. A structural unit ofZSM39 inclusion compound showin the 12-hedron with the
water molecule having occupancy of 0.5 and the 16-hedron wit>>h the template in one of
its four orientation having occupancy of 0.125.
I But LSoc.Cat. Cien.),VoLXIII,Num.1,1992
SYNCHROTRON X-RAYSTRUCTURE OFA ZEOLITE 123
Table 2. Interatomic distances and angles between atoms in ZSM39
DIST. S.D.
S11 - 01 1.5183 0.0120
- 02 1.5563 0.0084
- 03 1.5594 0.0104
- 09 1.5653 0.0105
Si2 - 02 1.5600 0.0087
- 05 1.5707 0.0089
- 04 1.5738 0.0028
- 07 1.6114 0.0089
5i3 - 07 1.5403 0.0089
- 03 1.5545 0.0105
- 08 1.5891 0.0096
- 06 1.5973 0.0104
Si4 - 06 1.5535 0.0103
- 08 1.5577 0.0096
- 09 1.5723 0.0106
- 05 1.5769 0.0089
5i5 - 4 01 1.5565 0.0120
01 - Si1 1.5183 0.0120
- Si5 1.5565 0.0120
02 - Si1 1.5563 0.0084
- Si2 1.5600 0.0087
03 - Si3 1.5545 0.0105
- Si1 1.5594 0.0104
04 - 2 Si2 1.5738 0.0028
05 - Si2 1.5707 0.0089
- Si4 1.5769 0.0089
06 - Si4 1.5535 0.0103
- Si3 1.5973 0.0104
07 - Si3 1.5403 0.0089
- Si2 1.6114 0.0089
08 - Si4 1.5577 0.0096
- Si3 1.5891 0.0096
09 - Sil 1.5653 0.0105
- Si4 1.5723 0.0106
[ButII.Soc.Cat . Cien .], VoI.XIII,N6m.1,1992
124 j. KA.AS1KtS, 1. Aft 1KAIAL \, Y. LO.AG, .V..ALLSO.A, A. ATICK
ATOM1 ATOM2 ATOMS ANGLE SD
01 Si5 01 107.17 0.94
O1 Si5 Ol 110.63 0.48
01 Si5 01 110.63 0.48
O1 Si5 Ol 110.63 0.48
01 Si5 Ol 110.63 0.48
O1 Si5 01 107.17 0.94
01 Sil 02 109.10 0.66
o l Si 1 03 108.95 0.77
O1 Sil 09 109.32 0.79
02 Sil 03 110.40 0.63
02 Sil 09 108.48 0.68
03 Si 1 09 1 1 0.57 0.56
02 Si2 04 112.39 0.73
02 Si2 05 108.05 0.58
02 Si2 07 107.22 0.58
04 Si2 05 109.94 0.46
04 Si2 07 109.61 0.45
05 Si2 07 109.57 0.49
03 Si3 06 110.02 0.53
03 Si3 07 108.77 0.55
03 Si3 08 108.52 0.55
06 513 07 109.40 0.51
06 Si3 08 110.96 0.50
07 Si3 08 109.14 0.52
05 Si4 06 111.20 0.52
05 Si4 08 109.25 0.52
05 S14 09 107.41 0.55
06 Si4 08 110.19 0.51
06 Si4 09 110.73 0.56
08 Si4 09 107.95 0.60
Si5 01 Sil 177.67 1.01
Sil 02 Si2 175.26 0.89
S11 03 Si3 179.61 0.85
Si2 04 Si2 174.91 1.14
Si2 05 Si4 169.35 0.69
Si3 06 Si4 175.62 0.62
Si2 07 Si3 170.30 0.69
Si3 08 Si4 168.59 0.71
Si l 09 Si4 177.10 0.94
1Budl.Soc.( it.(.ICn.1,VOI .XI1l,Num.1,1992
S1'.A (.'IIRO/RO.A .A'-R.-1 )'.STRL'C:TCRF OFA ZFOLITt 125
The template molecule structure was included in the refinement as a rigid
group applying to it different starting orientations and occupancy factors. The
adamantanium template is distorted and non - stoichiometrically distributed in
the cavity (Figure 5).
As shown in Table 2 the T-atom environments are very close to tetrahedral
angles and Si - O - Si angles are exceptionally large ranging from 168 to 180".
Fig. 5. Stereoscopic presentation of the 1-methyl
-1,3,5,7-tetra-azaadamanran- l-ium
with 4-bar symmetry applied to it in the 16-hedron.
[ButlISoc.Cat .CiCn.],Vol.XII1, Num.1,1992
126 J. KANSIKAS, I. MUTIKAINEN, Y. LONG, M. NELSON, A. KVICK
REFERENCES
[1] J.L. SCHLENKFR, F.G. DWYER, E.E. JENKINS, W.J. ROHRBAUGH, G.T. KOKO-
TAILO and W.M. METER, Nature 294 (1982) 340.
[2] L.B. McCusker, Acta Crystallogr. A47 (1991) 297.
[3] R. K. MCMuI.IAN, F. TAKUSAGAWA and T.C.W. MAK, J. Inclusion Phenomena,
6 (1988) 515.
[4] Y. LONG, H. HE, P. ZHENG, G. Wu and B. WANG Ibid. 5, (1987) 355.
[ BntII.Soc.Cat. Cien. ),VoI.XI I I,N6m.1,1992


Synchrotron X-ray structure of a zeolite ZSM-39 analogue

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