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Synthesis and structure refinement of ZSM—5 single crystals
Short Papers
Based upon local symmetry arguments it is possible to propose tentative assignments of the resonances to the various T-atoms. Consider the idealized Z S M - 1 2 fragment abstracted from the structurO and consisting of only T1, T2, T3, T4, and T5 (inset, Figure 1). It is evident that T1 is symmetrically equivalent to T2, that T3 is equivalent to T4 and that.each pair (T1/T2 and T3/T4) would be expected to give rise to a single resonance line in the silicon-29 n.m.r, spectrum. Melchior et al. 6 have shown that in A-type zeolites silicons present in 4-rings are shielded relative to those in faujasites in which the silicons are in 6-rings. Assuming that this is a general phenomenon, we ascribe the highest field resonance at -112.9 ppm which has a relative intensity of 2 to T1/T2 which are found in 4-rings. Thus the remaining resonance which has a relative intensity of 2 at -111.5 ppm is assigned to T 3 / T 4 which are adjacent to 4-rings and are identical in the building block. The lowest field peak at -109.3 ppm is assigned to T5 of this idealized building block, as well
as T6, and T7. Each of these silicons is two T-atoms removed from the 4-rings. It must be realized that these assignments are highly speculative and should be taken as such until confirmed by other techniques. Nevertheless these assignments represent our best effort in light of the available data.
REFERENCES 1 LaPierre, R. B., Rohrman, Jr., A. C., Schlenker, J. L., Wood, J. D., Rubin, M. K. and Rohrbaugh, W. J., submitted to Zeofites 2 Fyfe, C. A., Gobbi, G. C., Klinowski, J., Thomas, J. M. and Ramdas, S. Nature 1982, 296, 530 3 Higgins, J. B., Woessner, D. E., Trewella, J. C. and Schlenker, J. L. Zeolites 1984, 4, 112 4 Schlenker, J. L., Dwyer, F. G., Jenkins, E. E., Rohrbaugh, W. J. and Kokotailo, G. T. Nature 1981, 294, 340 5 Rosinski, E. J. and Rubin, M. K. US Pat. 3 832 449 (August 27, 1974) 6 Melchior, M. T., Vaughan, D. E. W., Jarman, R. H. and Jacobson, A. J. Nature 1982, 298, 455
Synthesis and structure refinement of Z S M - 5 single crystals H . L e r m e r , M. D r a e g e r , J . Steffen and K. K. Unger
Institut fuer Anorganische Chemic und Analytische Chemic, Johannes Gutenberg- Universitaet, 6500 Mainz, FRG Single crystals of Z S M - 5 of up to 280 #m were synthesized. An X-ray structure analysis was performed on one such crystal, and precise atomic positions and an R-factor of 0.0965 were measured. Keywords: ZSM-5; single crystal; X-ray structure analysis
INTRODUCTION The synthetic zeolites ZSM-5 ~ possess a structure not found in natural zeolites; however, detailed structural analysis by X-ray diffraction methods using single crystals has been hampered ~,3 by difficulties in obtaining suitably large crystals. This paper reports on an improved synthesis (based on earlier methods 4,5) whereby Z S M - 5 single crystals of up to 280/zm can be obtained. The reaction mixture used in the present work has the following molar composition: SiO2: NaAIO2: N a O H : TPABr : 12.2 1 43.2 43.2
H20 1994
whereby the silica component was Aerosil TT600 (Degussa), TPABr (tetrapropylammonium bromide) p.a. was supplied by Serva, and sodium aluminate and sodium hydroxide p.a. were products from Riedel de Haen and Merck, respectively. 0 1 4 4 - 2 4 4 9 / 8 5 / 0 3 0 1 3 1 - 0 4 $03.00 © 1985 Butterworth & Co. (Publishers) Ltd.
The preparation of this mixture was carried out as follows: Two mixtures were prepared, mixture I containing the Aerosil and TPABr, and mixture II containing sodium aluminate, whereby the water and sodium hydroxide components were divided equally between the two mixtures. Mixture I was stirred at 320 K for 30 min and then the clear solution of mixture II was added quickly under intensive stirring. The resulting reaction mixture was maintained at 460 K for ten days in a Teflon-coated autoclave (130 ml). Large single crystals of Z S M - 5 were thus obtained, along with analcime and a - q u a r t z (see Figure 1). The ratio of silicon to aluminium was measured at 11.9:1 using EDS (energy dispersive spectroscopy). The X-ray structure analysis was carried out on a crystal of pyramidal form, measuring 260x130x120/zm (see Figure 2). Although this crystal form is unusual for
Figure 1 Single crystal of Z S M - 5 , surrounded by analcime and ¢x-quartz. Scale--bar=lO #m
ZEOLITES, 1985, Vol 5, May
131
Short Papers
Z S M - 5 , it was nevertheless chosen for the analysis because of its size and good quality. M e a s u r e m e n t s on the single crystal using Weissenberg and Precession cameras yielded o r t h o r h o m b i c s y m m e t r y and the space g r o u p Pnma (No. 62) 6 or Pn21a (No. 33) 6. T h e crystal faces were indexed using a double rotating reflection goniometer (Figure 2). T h e following exact lattice constants were obtained using a four circle diffractometer ( E n r a f - N o n i u s ) with M o K a radiation.
A total of 10928 reflections in 1/8 of the reciprocal space were m e a s u r e d in ~o/20-scan m o d e in the range 0 =1 ° to 32.5 °. T h e r e r e m a i n e d 2217 reflections with an intensity > 2o after intensity correction. A s y m m e t r y test 7 was carried out on both the above crystal and a second crystal from a separate synthesis, in o r d e r to verify the L a u e s y m m e t r y m m m, w h e r e b y the 115 strongest reflections were m e a s u r e d in the region ~ = 2 0 ° - 3 2 ° using M o K a radiation. Eight orthor h o m b i c equivalent reflections gave R values of 0.0215 and 0.0223 respectively.
a: 2007.6+0.1 p m b: 1992.6+0.1 p m c: 1340.1_+0.1 p m
R~y,. =
/" ?- 0 ~
I 0 0
/ ~
302
/" 2 0
V
_•/Y.
"
: summed
over
all reflections
T h e lattice constants of the second Z S M - 5 crystal were s o m e w h a t larger, the difference being just on the limits of analytical significance:
O'130mm c ,
a: 2009.2+0.3 p m b: 1995.2+0.2 p m
Figure 2 Measurements of the crystal studied showing the indexed faces
Atom
Y~.
_
O. 2 6 0 mm
Table 1
~.. : s u m m e d over i-,.q equivalent reflections
n i-eq
Height=0.120 mm
/
~o2
]~ W (F,,,.,~ - F)'-' ,, i-,.q ' Y. W F e
c: 1341.4+0.2 p m
Position parameters and temperature factors of the atoms in the SBU
X
Y
Z
0.0574(2) 0.0275(2) 0.0611(2) 0.0637(2) 0.0274(2) 0.0594(2) -0.1717(2) -0.1300(2) -0.1728(2) -0.1727(2) -0.1302(2) -0.1731(2) 0.0561(9) 0.0585(6) 0,0608(8) 0.0641(7) 0.0520(8) 0.0556(9) - 0.1546(7) -0.1547(7) -0.1545(6) - 0.1578(8) - 0.1583(9) -0.1562(8) -0.0518(8) - 0.0527(8) 0.1275(7) - 0.0006(7) -0.1312(7) 0.1306(6) 0.0002(7) -0.1291(7) 0,0527(7) -0.1495(6) 0.25000 0.25000 0.25000 0.25000 0.25000 0.25000
- 0 . 3 3 5 8 ( 3) -0.1880( 3) 0.0328( 3) 0.0270( 3) - 0 . 1 8 4 6 ( 4) - 0 . 3 2 6 1 ( 3) - 0 . 3 2 5 3 ( 4) - 0 . 1 8 4 1 ( 3) 0.0315( 3) 0.0303( 4) - 0 . 1 8 1 2 ( 4) -0.3177(4) -0.2443(10) - 0 . 0 7 6 3 ( 9) 0.0330(12) -0.0836(10) -0.2744(10) -0.2447(10) - 0.2365(10) -0.0711(10) 0.0263( 9) -0.0776(12) -0.2677(11) -0.2404(13) -0.1853(12) -0.1744(10) -0.3904(11) -0.4134(10) -0.4258(10) - 0 . 3 8 2 0 ( 9) -0.4059(11) -0.4185(11) - 0 . 2 0 8 0 ( 9) - 0 . 2 0 4 9 ( 9) 0.1482(14) 0.1508(13) 0.5596(12) 0.5624(15) 0.8357(79) 0.8814(49)
T1 T2 T3 T4 T5 T6 T7 T8 T9 TIO Tll T12 01 02 03 04 05 06 07 08 09 010 011 012 013 014 015 016 017 018 019 O20 021 022 023 024 O25 026 OXl OX2
0.4223( 2) 0.3082( 2) 0.2792( 2) 0.1219( 2) 0.0716( 2) 0.1869( 2) 0.4230( 2) 0.3074( 2) 0.2749( 2) O. 1205( 2) 0,0701 ( 2) 0.1876( 2) 0,3711 ( 6) 0.3111( 6) 0.2005( 8) 0.0945( 6) 0.1152( 6) 0.2442( 7) 0,3750( 6) 0.3072(7) 0.1977(6) 0.0893(8) 0.1182(7) 0.2451 ( 7 ) 0.3O65(8) 0.0758(6) 0.4172(7) 0.4099 6) 0.4006 7) 0.1890 6) 0.1921q 7) 0.1944~ 7) - 0.0024, 6) -0.0051, 6) 0.0801 9) 0.3134 9) 0.2144 8) 0.3905 9) 0.3031 (42) 0.4850(32)
132
ZEOLITES, 1985, Vol 5, May
Ull 0,014( 1) 0,021( 2) 0,015( 1) 0,014( 1) 0,009( 1) 0,015( 1) 0,013( 1) 0,017( 2) 0,016( 1) 0,021( 2) 0.013( 2) 0.018(2) 0.039( 3) 0.031( 2) 0,054( 4) 0.032( 3) 0.030(2) 0,039( 3) 0.029( 2) 0.039( 3) 0.030( 2) 0.049( 4) 0.040( 3) 0.044( 4) 0.053( 3) 0.039( 3) 0.035( 3) 0.035( 3) 0.035( 3) 0.029( 2) 0.042(3) 0.037( 3) 0.027( 2) 0,024( 2) 0.028( 4) 0.027( 4) 0.022( 3) 0.033( 4) 0.320(44) 0.242(31 )
U22
U33
U23
U13
0.010(1) 0,014(1) 0.016(2) 0,007(2) 0.015(1) 0.014(1) 0.014(2) 0.021(1) 0.011(1) 0.016(2) 0.013(1) 0,013(1)
0.015(2) 0.019(2) 0,020(2) 0.013(2) 0.014(2) 0.015(1) 0.019(2) 0.012(1) 0.016(2) 0.018(2) 0.020(2) 0.021(2)
-0.003(2) -0,001(1) 0.002(2) -0.002(1) -0.001(1) 0,006(2) 0,000(2) 0.001(1) 0.002(2) -0.000(2) 0.000(2) -0,002(1)
-0,004(1) 0,008(2) -0.000(1) -0.001(1) 0.001(1) 0.000(1) 0.001(1) 0,001(2) -0,000(1) 0.002(1) 0.000(1) 0.006(2)
o~6 09 TIO
/o,o o22---_/..... /
oo/7"-<
/025 T9
\
\02
\
\ o, J.
021
/
018
\
019
rl--------ol 5 /
016
U12 0.000(1) 0.002(1) 0.001(1) -0,001(1) -0.000(1) 0.001(2) -0.001(1) 0,000(2) -0.001(1) -0.001(1) 0,004(1) -0.002(1)
S h o r t Papers
T h e intensities of the reflections of both crystals were identical. T h e positions of the T-atoms (Si, AI) and oxygen atoms were determined by use of literature data 3 and subsequent Fourier synthesis 7, whereby all T-atoms were treated as silicon. Differential Fourier synthesis showed two nonframework peaks. In analogy to published work :~ these were refined using the scattering factors for oxygen, and labelled as Ox 1 and Ox 2. T h e diffractometer data was subjected to an adsorption correction based on the known dimensions of the crystal and the indices of the crystal faces (Figure 2). T h e atomic positions were refined using least-squares methods 7, whereby for the T-atoms anisotropic t e m p e r a t u r e factors were taken into consideration. T h e space group Pnrna (No. 62) 6 was confirmed on the basis Table 2
T - O bond lengths (in p m ) "
Atom I
Atom J
T 1A T 1A T 1A T 1A T 2A T 2A T 2A T 2A T 3A T 3A T 3A T 3A T 4A T 4A T 4A T 4A T 5A T 5A T 5A T 5A T 6A T 6A T6A T 6A T 7A T 7A T 7A T 7A T 8A T 8A T 8A T 8A T 9A T 9A T 9A T 9A T IOA T IOA T IOA T IOA T 11A T 11A T 11A T 11A T 12A T 12A T 12A T 12A
O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O
1A 15A 16A 21B 1A 2A 6A 13A 2A 3A 19B 20B 3A 4A 168 178 4A 5A 14A 21A 5A 6A 18A 19A 7A 17A 22B 23B 7A 8A 12A 13A 8A 9A 18B 25B 9A IOA 15B 26B IOA 11A 14A 22A 11A 12A 20A 24B
Distance IJ 160(2) 158(2) 158(2) 162(2) 158(2) 162(2) 159(2) 158(2) 160(2) 158(2) 158(2) 159(2) 158(2) 158(2) 162(2) 155(2) 161(2) 157(2) 161(2) 160(2) 160(2) 159(2) 161(2) 159(2) 157(2) 163(2) 156(2) 160(1) 160(2) 159(2) 155(2) 156(2) 156(2) 159(2) 160(2) 157(1) 160(2) 160(2) 159(2) 161(1) 154(2) 161(2) 155(2) 159(2) 157(2) 159(2) 162(2) 159(1)
" B are several neighbouring s e c o n d a r y building units r e s p e c t i v e l y to A
of various tests and the refinement of the data. A conventional R-factor of 0.0965 was obtained after several refining cycles. Table 1 shows the atomic positions in the SBU. Table 2 a lists the T - - O bond lengths.
Table 3
O - - T - - O bond angles (in o)
O1--T1--O15 O1--T1--O16 O1--T1-O21 O15--T1--O16 O15--T1--O21 O16--T1--O21 O1--T2--O2 O1--T2--O6 O1--T2--O13 O2--T2--O6 O2--T2--O13 O6--T2--O13 O2--T3--O3 O2--T3--O19 O2--T3--O20 O3--T3--O19 O3--T3--O20 O19--T3--O20 O3--T4--O4 O3--T4--O16 O3--T4--O17 O4--T4--O16 O4--T4--O17 O16--T4--O17 O4--T5--O5 O4--T5--O14 O4--T5--O21 O5--T5--O14 O5--T5--O21 O14--T5--O21 O5--T6--O6 O5--T6--O18 O5--T6--O19 O6--T6--O18 O6--T6--O19 O18--T6--O19
Table4
: : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : :
109.1(9) 113.1(9) 108.6(7) 109.5(8) 106.2(8) 110.2(8) 106.0(8) 106.9(8) 112.9(9) 109.6(8) 111.2(8) 110.1(9) 113.7(8) 107.7(8) 105.6(8) 111.0(9) 109.5(9) 109.0(8) 113.2(8) 109.9(8) 107.5(8) 109.2(8) 106.0(8) 110.9(8) 110.2(8) 111.5(8) 106.8(7) 110.3(8) 105.6(7) 112.3(8) 110.4(8) 107.8(8) 106.4(8) 110.1(9) 112.2(9) 109.8(8)
T--O--Tbond
T1--O1--T2 T 2 - - O 2 - - T3 T 3 - - O 3 - - T4 T 4 - - O 4 - - T5 T 5 - - O 5 - - T6 T 2 - - O 6 - - T6 T 7 - - O 7 - - T8 T 8 - - O 8 - - T9 T9--O9--T10 T10--O10--T11 T11--O11--T12 T8--O12--T12 T2--O13--T8 T5--O14--T11 T1--O15--T10 T1--O16--T4 T 4 - - O 1 7 - - T7 T 6 - - O 1 8 - - T9 T3--O19--T6 T3--O20--T12 T 5 - - O 2 1 - - T1 TT--O22--T11 T7--O23--T7' T12--O24--T12" T9--O25--T9' T10--O26--T10'
: : : : : : : : : : : : : : : : : : : : : : : : : :
O7--T7--O17 O7--T7--O23 O7--T7--O22 O17--T7--O23 O17--T7--O22 O23--T7--O22 O7-- T8--O8 O7--T8--O12 O7--T8--O13 O8--T8--O12 O8--T8--O13 O12--T8--O13 O8--T9--O9 O8--T9--O25 O8--T9--O18 O9--T9--O25 O9--T9--O18 O25--T9--O18 O9--T10--O10 O9--T10--O26 O9--T10--O15 O10--T10--O26 O10--T10--O15 O26--T10--O15 O10--Tll--Oll O10--Tll--O14 O10--Tll--O22 Oll--Tll--O14 Oll--Tll--O22 O14--Tll--O22 Oll--T12--O12 Oll--T12--O20 Oll--T12--O24 O12--T12--O20 O12--T12--O24 O20--T12--O24
angles (in o)
152.5(12) 147.6(9) 176.2(12) 152.6(10) 149.5(10) 158.2(13) 156.6(10) 155.4(11) 153.2(9) 167.3(12) 154.5(11) 167.2(13) 178.0(12) 169.0(10) 147.6(11) 163.2(10) 147.5(10) 144.3(10) 160.7(11) 146.2(10) 144.2(9) 153.3(9) 154.0(14) 149.2(13) 148.5(12) 145.1(14)
: : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : :
110.5(8) 110.8(9) 108,0(7) 106.7(9) 109.2(7) 111.7(8) 108.9(8) 111.5(9) 108.1(8) 110.9(9) 108.6(9) 108.8(9) 108.2(8) 107.7(9) 109.2(8) 111.3(8) 110.5(7) 109.9(8) 107.9(8) 111.1(8) 111.0(8) 111.3(10) 108.2(9) 107.3(9) 112.0(9) 106.5(9) 109.3(8) 110.2(9) 109.9(8) 108.9(7) 109.1(9) 109.1(9) 106.4(10) 111.7(9) 112.8(10) 107.7(9)
Short Papers
T h e O - - T - - O bond angles with an average value of 109°+2 ° lie in the range expected for tetrahedral angles. T h e values are scattered between 105°-113 °. Table 38 shows the calculated angles with standard deviations. T h e T - - O - - T angles are listed in Table 4a; notable are the large angles in the ring 7-2-- 7 3 - - T 4 - - 7"5-- T6 between 7 " 3 - - O 4 - - T 4 (176.2 °) and in the oxygen bridge 72 - O13 - 78 (178.0°). The results confirm the structural model used for Z S M - 5 z'3. T h e R-factor found in the present work is distinctly improved. The T - - O bond lengths were found to be 159. pm on average without any significant scatter. Additional m a t e r i a l Tables showing exact evaluations of coordination polyhedra and the 5-1 ring units as well as observed and calculated structure factors can be obtained from the authors on request.
Note This work was supported by the B M F T (project No. 03C121), and contains excerpts from forthcoming dissertations of H. L e r m e r and J. Steffen.
REFERENCES 1 Argauer, R. J. and Landolt, G. E. U.S. Pat. 3 702 886 (1972) 2 Kokotailo, G. T., Lawton, S. L., Olson, D. H. and Meier, W. M. Nature (London) 1978, 272, 437 3 0 l s o n , D. H., Kokotailo, G. T., Lawton, S. L. and Meier, W. M. J. Phys. Chem. 1981, 86, 2238 4 von Ballmoos, R. R. -thesis ETH Zurich (1981) 5 von Ballmoos, R. and Meier, W. M. Nature (London) 1981, 289, 782 6 'Int. Tables for X-Ray Crystallography', Vol. 1, The Kynoch Press, Birmingham, 1969 7 Sheldrick, G., SHELX-76, Program for Crystal Structure Determination, Cambridge 1976 8 Busing, W. R., Martin, K. O. and Levy, H. A., Oak Ridge 1964; modified by M. Draeger, Mainz, Program ORFFE
(Received 13 April 1984; revised 11 J a n u a r y 1985)
Based upon local symmetry arguments it is possible to propose tentative assignments of the resonances to the various T-atoms. Consider the idealized Z S M - 1 2 fragment abstracted from the structurO and consisting of only T1, T2, T3, T4, and T5 (inset, Figure 1). It is evident that T1 is symmetrically equivalent to T2, that T3 is equivalent to T4 and that.each pair (T1/T2 and T3/T4) would be expected to give rise to a single resonance line in the silicon-29 n.m.r, spectrum. Melchior et al. 6 have shown that in A-type zeolites silicons present in 4-rings are shielded relative to those in faujasites in which the silicons are in 6-rings. Assuming that this is a general phenomenon, we ascribe the highest field resonance at -112.9 ppm which has a relative intensity of 2 to T1/T2 which are found in 4-rings. Thus the remaining resonance which has a relative intensity of 2 at -111.5 ppm is assigned to T 3 / T 4 which are adjacent to 4-rings and are identical in the building block. The lowest field peak at -109.3 ppm is assigned to T5 of this idealized building block, as well
as T6, and T7. Each of these silicons is two T-atoms removed from the 4-rings. It must be realized that these assignments are highly speculative and should be taken as such until confirmed by other techniques. Nevertheless these assignments represent our best effort in light of the available data.
REFERENCES 1 LaPierre, R. B., Rohrman, Jr., A. C., Schlenker, J. L., Wood, J. D., Rubin, M. K. and Rohrbaugh, W. J., submitted to Zeofites 2 Fyfe, C. A., Gobbi, G. C., Klinowski, J., Thomas, J. M. and Ramdas, S. Nature 1982, 296, 530 3 Higgins, J. B., Woessner, D. E., Trewella, J. C. and Schlenker, J. L. Zeolites 1984, 4, 112 4 Schlenker, J. L., Dwyer, F. G., Jenkins, E. E., Rohrbaugh, W. J. and Kokotailo, G. T. Nature 1981, 294, 340 5 Rosinski, E. J. and Rubin, M. K. US Pat. 3 832 449 (August 27, 1974) 6 Melchior, M. T., Vaughan, D. E. W., Jarman, R. H. and Jacobson, A. J. Nature 1982, 298, 455
Synthesis and structure refinement of Z S M - 5 single crystals H . L e r m e r , M. D r a e g e r , J . Steffen and K. K. Unger
Institut fuer Anorganische Chemic und Analytische Chemic, Johannes Gutenberg- Universitaet, 6500 Mainz, FRG Single crystals of Z S M - 5 of up to 280 #m were synthesized. An X-ray structure analysis was performed on one such crystal, and precise atomic positions and an R-factor of 0.0965 were measured. Keywords: ZSM-5; single crystal; X-ray structure analysis
INTRODUCTION The synthetic zeolites ZSM-5 ~ possess a structure not found in natural zeolites; however, detailed structural analysis by X-ray diffraction methods using single crystals has been hampered ~,3 by difficulties in obtaining suitably large crystals. This paper reports on an improved synthesis (based on earlier methods 4,5) whereby Z S M - 5 single crystals of up to 280/zm can be obtained. The reaction mixture used in the present work has the following molar composition: SiO2: NaAIO2: N a O H : TPABr : 12.2 1 43.2 43.2
H20 1994
whereby the silica component was Aerosil TT600 (Degussa), TPABr (tetrapropylammonium bromide) p.a. was supplied by Serva, and sodium aluminate and sodium hydroxide p.a. were products from Riedel de Haen and Merck, respectively. 0 1 4 4 - 2 4 4 9 / 8 5 / 0 3 0 1 3 1 - 0 4 $03.00 © 1985 Butterworth & Co. (Publishers) Ltd.
The preparation of this mixture was carried out as follows: Two mixtures were prepared, mixture I containing the Aerosil and TPABr, and mixture II containing sodium aluminate, whereby the water and sodium hydroxide components were divided equally between the two mixtures. Mixture I was stirred at 320 K for 30 min and then the clear solution of mixture II was added quickly under intensive stirring. The resulting reaction mixture was maintained at 460 K for ten days in a Teflon-coated autoclave (130 ml). Large single crystals of Z S M - 5 were thus obtained, along with analcime and a - q u a r t z (see Figure 1). The ratio of silicon to aluminium was measured at 11.9:1 using EDS (energy dispersive spectroscopy). The X-ray structure analysis was carried out on a crystal of pyramidal form, measuring 260x130x120/zm (see Figure 2). Although this crystal form is unusual for
Figure 1 Single crystal of Z S M - 5 , surrounded by analcime and ¢x-quartz. Scale--bar=lO #m
ZEOLITES, 1985, Vol 5, May
131
Short Papers
Z S M - 5 , it was nevertheless chosen for the analysis because of its size and good quality. M e a s u r e m e n t s on the single crystal using Weissenberg and Precession cameras yielded o r t h o r h o m b i c s y m m e t r y and the space g r o u p Pnma (No. 62) 6 or Pn21a (No. 33) 6. T h e crystal faces were indexed using a double rotating reflection goniometer (Figure 2). T h e following exact lattice constants were obtained using a four circle diffractometer ( E n r a f - N o n i u s ) with M o K a radiation.
A total of 10928 reflections in 1/8 of the reciprocal space were m e a s u r e d in ~o/20-scan m o d e in the range 0 =1 ° to 32.5 °. T h e r e r e m a i n e d 2217 reflections with an intensity > 2o after intensity correction. A s y m m e t r y test 7 was carried out on both the above crystal and a second crystal from a separate synthesis, in o r d e r to verify the L a u e s y m m e t r y m m m, w h e r e b y the 115 strongest reflections were m e a s u r e d in the region ~ = 2 0 ° - 3 2 ° using M o K a radiation. Eight orthor h o m b i c equivalent reflections gave R values of 0.0215 and 0.0223 respectively.
a: 2007.6+0.1 p m b: 1992.6+0.1 p m c: 1340.1_+0.1 p m
R~y,. =
/" ?- 0 ~
I 0 0
/ ~
302
/" 2 0
V
_•/Y.
"
: summed
over
all reflections
T h e lattice constants of the second Z S M - 5 crystal were s o m e w h a t larger, the difference being just on the limits of analytical significance:
O'130mm c ,
a: 2009.2+0.3 p m b: 1995.2+0.2 p m
Figure 2 Measurements of the crystal studied showing the indexed faces
Atom
Y~.
_
O. 2 6 0 mm
Table 1
~.. : s u m m e d over i-,.q equivalent reflections
n i-eq
Height=0.120 mm
/
~o2
]~ W (F,,,.,~ - F)'-' ,, i-,.q ' Y. W F e
c: 1341.4+0.2 p m
Position parameters and temperature factors of the atoms in the SBU
X
Y
Z
0.0574(2) 0.0275(2) 0.0611(2) 0.0637(2) 0.0274(2) 0.0594(2) -0.1717(2) -0.1300(2) -0.1728(2) -0.1727(2) -0.1302(2) -0.1731(2) 0.0561(9) 0.0585(6) 0,0608(8) 0.0641(7) 0.0520(8) 0.0556(9) - 0.1546(7) -0.1547(7) -0.1545(6) - 0.1578(8) - 0.1583(9) -0.1562(8) -0.0518(8) - 0.0527(8) 0.1275(7) - 0.0006(7) -0.1312(7) 0.1306(6) 0.0002(7) -0.1291(7) 0,0527(7) -0.1495(6) 0.25000 0.25000 0.25000 0.25000 0.25000 0.25000
- 0 . 3 3 5 8 ( 3) -0.1880( 3) 0.0328( 3) 0.0270( 3) - 0 . 1 8 4 6 ( 4) - 0 . 3 2 6 1 ( 3) - 0 . 3 2 5 3 ( 4) - 0 . 1 8 4 1 ( 3) 0.0315( 3) 0.0303( 4) - 0 . 1 8 1 2 ( 4) -0.3177(4) -0.2443(10) - 0 . 0 7 6 3 ( 9) 0.0330(12) -0.0836(10) -0.2744(10) -0.2447(10) - 0.2365(10) -0.0711(10) 0.0263( 9) -0.0776(12) -0.2677(11) -0.2404(13) -0.1853(12) -0.1744(10) -0.3904(11) -0.4134(10) -0.4258(10) - 0 . 3 8 2 0 ( 9) -0.4059(11) -0.4185(11) - 0 . 2 0 8 0 ( 9) - 0 . 2 0 4 9 ( 9) 0.1482(14) 0.1508(13) 0.5596(12) 0.5624(15) 0.8357(79) 0.8814(49)
T1 T2 T3 T4 T5 T6 T7 T8 T9 TIO Tll T12 01 02 03 04 05 06 07 08 09 010 011 012 013 014 015 016 017 018 019 O20 021 022 023 024 O25 026 OXl OX2
0.4223( 2) 0.3082( 2) 0.2792( 2) 0.1219( 2) 0.0716( 2) 0.1869( 2) 0.4230( 2) 0.3074( 2) 0.2749( 2) O. 1205( 2) 0,0701 ( 2) 0.1876( 2) 0,3711 ( 6) 0.3111( 6) 0.2005( 8) 0.0945( 6) 0.1152( 6) 0.2442( 7) 0,3750( 6) 0.3072(7) 0.1977(6) 0.0893(8) 0.1182(7) 0.2451 ( 7 ) 0.3O65(8) 0.0758(6) 0.4172(7) 0.4099 6) 0.4006 7) 0.1890 6) 0.1921q 7) 0.1944~ 7) - 0.0024, 6) -0.0051, 6) 0.0801 9) 0.3134 9) 0.2144 8) 0.3905 9) 0.3031 (42) 0.4850(32)
132
ZEOLITES, 1985, Vol 5, May
Ull 0,014( 1) 0,021( 2) 0,015( 1) 0,014( 1) 0,009( 1) 0,015( 1) 0,013( 1) 0,017( 2) 0,016( 1) 0,021( 2) 0.013( 2) 0.018(2) 0.039( 3) 0.031( 2) 0,054( 4) 0.032( 3) 0.030(2) 0,039( 3) 0.029( 2) 0.039( 3) 0.030( 2) 0.049( 4) 0.040( 3) 0.044( 4) 0.053( 3) 0.039( 3) 0.035( 3) 0.035( 3) 0.035( 3) 0.029( 2) 0.042(3) 0.037( 3) 0.027( 2) 0,024( 2) 0.028( 4) 0.027( 4) 0.022( 3) 0.033( 4) 0.320(44) 0.242(31 )
U22
U33
U23
U13
0.010(1) 0,014(1) 0.016(2) 0,007(2) 0.015(1) 0.014(1) 0.014(2) 0.021(1) 0.011(1) 0.016(2) 0.013(1) 0,013(1)
0.015(2) 0.019(2) 0,020(2) 0.013(2) 0.014(2) 0.015(1) 0.019(2) 0.012(1) 0.016(2) 0.018(2) 0.020(2) 0.021(2)
-0.003(2) -0,001(1) 0.002(2) -0.002(1) -0.001(1) 0,006(2) 0,000(2) 0.001(1) 0.002(2) -0.000(2) 0.000(2) -0,002(1)
-0,004(1) 0,008(2) -0.000(1) -0.001(1) 0.001(1) 0.000(1) 0.001(1) 0,001(2) -0,000(1) 0.002(1) 0.000(1) 0.006(2)
o~6 09 TIO
/o,o o22---_/..... /
oo/7"-<
/025 T9
\
\02
\
\ o, J.
021
/
018
\
019
rl--------ol 5 /
016
U12 0.000(1) 0.002(1) 0.001(1) -0,001(1) -0.000(1) 0.001(2) -0.001(1) 0,000(2) -0.001(1) -0.001(1) 0,004(1) -0.002(1)
S h o r t Papers
T h e intensities of the reflections of both crystals were identical. T h e positions of the T-atoms (Si, AI) and oxygen atoms were determined by use of literature data 3 and subsequent Fourier synthesis 7, whereby all T-atoms were treated as silicon. Differential Fourier synthesis showed two nonframework peaks. In analogy to published work :~ these were refined using the scattering factors for oxygen, and labelled as Ox 1 and Ox 2. T h e diffractometer data was subjected to an adsorption correction based on the known dimensions of the crystal and the indices of the crystal faces (Figure 2). T h e atomic positions were refined using least-squares methods 7, whereby for the T-atoms anisotropic t e m p e r a t u r e factors were taken into consideration. T h e space group Pnrna (No. 62) 6 was confirmed on the basis Table 2
T - O bond lengths (in p m ) "
Atom I
Atom J
T 1A T 1A T 1A T 1A T 2A T 2A T 2A T 2A T 3A T 3A T 3A T 3A T 4A T 4A T 4A T 4A T 5A T 5A T 5A T 5A T 6A T 6A T6A T 6A T 7A T 7A T 7A T 7A T 8A T 8A T 8A T 8A T 9A T 9A T 9A T 9A T IOA T IOA T IOA T IOA T 11A T 11A T 11A T 11A T 12A T 12A T 12A T 12A
O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O
1A 15A 16A 21B 1A 2A 6A 13A 2A 3A 19B 20B 3A 4A 168 178 4A 5A 14A 21A 5A 6A 18A 19A 7A 17A 22B 23B 7A 8A 12A 13A 8A 9A 18B 25B 9A IOA 15B 26B IOA 11A 14A 22A 11A 12A 20A 24B
Distance IJ 160(2) 158(2) 158(2) 162(2) 158(2) 162(2) 159(2) 158(2) 160(2) 158(2) 158(2) 159(2) 158(2) 158(2) 162(2) 155(2) 161(2) 157(2) 161(2) 160(2) 160(2) 159(2) 161(2) 159(2) 157(2) 163(2) 156(2) 160(1) 160(2) 159(2) 155(2) 156(2) 156(2) 159(2) 160(2) 157(1) 160(2) 160(2) 159(2) 161(1) 154(2) 161(2) 155(2) 159(2) 157(2) 159(2) 162(2) 159(1)
" B are several neighbouring s e c o n d a r y building units r e s p e c t i v e l y to A
of various tests and the refinement of the data. A conventional R-factor of 0.0965 was obtained after several refining cycles. Table 1 shows the atomic positions in the SBU. Table 2 a lists the T - - O bond lengths.
Table 3
O - - T - - O bond angles (in o)
O1--T1--O15 O1--T1--O16 O1--T1-O21 O15--T1--O16 O15--T1--O21 O16--T1--O21 O1--T2--O2 O1--T2--O6 O1--T2--O13 O2--T2--O6 O2--T2--O13 O6--T2--O13 O2--T3--O3 O2--T3--O19 O2--T3--O20 O3--T3--O19 O3--T3--O20 O19--T3--O20 O3--T4--O4 O3--T4--O16 O3--T4--O17 O4--T4--O16 O4--T4--O17 O16--T4--O17 O4--T5--O5 O4--T5--O14 O4--T5--O21 O5--T5--O14 O5--T5--O21 O14--T5--O21 O5--T6--O6 O5--T6--O18 O5--T6--O19 O6--T6--O18 O6--T6--O19 O18--T6--O19
Table4
: : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : :
109.1(9) 113.1(9) 108.6(7) 109.5(8) 106.2(8) 110.2(8) 106.0(8) 106.9(8) 112.9(9) 109.6(8) 111.2(8) 110.1(9) 113.7(8) 107.7(8) 105.6(8) 111.0(9) 109.5(9) 109.0(8) 113.2(8) 109.9(8) 107.5(8) 109.2(8) 106.0(8) 110.9(8) 110.2(8) 111.5(8) 106.8(7) 110.3(8) 105.6(7) 112.3(8) 110.4(8) 107.8(8) 106.4(8) 110.1(9) 112.2(9) 109.8(8)
T--O--Tbond
T1--O1--T2 T 2 - - O 2 - - T3 T 3 - - O 3 - - T4 T 4 - - O 4 - - T5 T 5 - - O 5 - - T6 T 2 - - O 6 - - T6 T 7 - - O 7 - - T8 T 8 - - O 8 - - T9 T9--O9--T10 T10--O10--T11 T11--O11--T12 T8--O12--T12 T2--O13--T8 T5--O14--T11 T1--O15--T10 T1--O16--T4 T 4 - - O 1 7 - - T7 T 6 - - O 1 8 - - T9 T3--O19--T6 T3--O20--T12 T 5 - - O 2 1 - - T1 TT--O22--T11 T7--O23--T7' T12--O24--T12" T9--O25--T9' T10--O26--T10'
: : : : : : : : : : : : : : : : : : : : : : : : : :
O7--T7--O17 O7--T7--O23 O7--T7--O22 O17--T7--O23 O17--T7--O22 O23--T7--O22 O7-- T8--O8 O7--T8--O12 O7--T8--O13 O8--T8--O12 O8--T8--O13 O12--T8--O13 O8--T9--O9 O8--T9--O25 O8--T9--O18 O9--T9--O25 O9--T9--O18 O25--T9--O18 O9--T10--O10 O9--T10--O26 O9--T10--O15 O10--T10--O26 O10--T10--O15 O26--T10--O15 O10--Tll--Oll O10--Tll--O14 O10--Tll--O22 Oll--Tll--O14 Oll--Tll--O22 O14--Tll--O22 Oll--T12--O12 Oll--T12--O20 Oll--T12--O24 O12--T12--O20 O12--T12--O24 O20--T12--O24
angles (in o)
152.5(12) 147.6(9) 176.2(12) 152.6(10) 149.5(10) 158.2(13) 156.6(10) 155.4(11) 153.2(9) 167.3(12) 154.5(11) 167.2(13) 178.0(12) 169.0(10) 147.6(11) 163.2(10) 147.5(10) 144.3(10) 160.7(11) 146.2(10) 144.2(9) 153.3(9) 154.0(14) 149.2(13) 148.5(12) 145.1(14)
: : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : :
110.5(8) 110.8(9) 108,0(7) 106.7(9) 109.2(7) 111.7(8) 108.9(8) 111.5(9) 108.1(8) 110.9(9) 108.6(9) 108.8(9) 108.2(8) 107.7(9) 109.2(8) 111.3(8) 110.5(7) 109.9(8) 107.9(8) 111.1(8) 111.0(8) 111.3(10) 108.2(9) 107.3(9) 112.0(9) 106.5(9) 109.3(8) 110.2(9) 109.9(8) 108.9(7) 109.1(9) 109.1(9) 106.4(10) 111.7(9) 112.8(10) 107.7(9)
Short Papers
T h e O - - T - - O bond angles with an average value of 109°+2 ° lie in the range expected for tetrahedral angles. T h e values are scattered between 105°-113 °. Table 38 shows the calculated angles with standard deviations. T h e T - - O - - T angles are listed in Table 4a; notable are the large angles in the ring 7-2-- 7 3 - - T 4 - - 7"5-- T6 between 7 " 3 - - O 4 - - T 4 (176.2 °) and in the oxygen bridge 72 - O13 - 78 (178.0°). The results confirm the structural model used for Z S M - 5 z'3. T h e R-factor found in the present work is distinctly improved. The T - - O bond lengths were found to be 159. pm on average without any significant scatter. Additional m a t e r i a l Tables showing exact evaluations of coordination polyhedra and the 5-1 ring units as well as observed and calculated structure factors can be obtained from the authors on request.
Note This work was supported by the B M F T (project No. 03C121), and contains excerpts from forthcoming dissertations of H. L e r m e r and J. Steffen.
REFERENCES 1 Argauer, R. J. and Landolt, G. E. U.S. Pat. 3 702 886 (1972) 2 Kokotailo, G. T., Lawton, S. L., Olson, D. H. and Meier, W. M. Nature (London) 1978, 272, 437 3 0 l s o n , D. H., Kokotailo, G. T., Lawton, S. L. and Meier, W. M. J. Phys. Chem. 1981, 86, 2238 4 von Ballmoos, R. R. -thesis ETH Zurich (1981) 5 von Ballmoos, R. and Meier, W. M. Nature (London) 1981, 289, 782 6 'Int. Tables for X-Ray Crystallography', Vol. 1, The Kynoch Press, Birmingham, 1969 7 Sheldrick, G., SHELX-76, Program for Crystal Structure Determination, Cambridge 1976 8 Busing, W. R., Martin, K. O. and Levy, H. A., Oak Ridge 1964; modified by M. Draeger, Mainz, Program ORFFE
(Received 13 April 1984; revised 11 J a n u a r y 1985)