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The crystal structure of the new double CuII complex salt, [Cu(L)(H2O)2][Cu(L)]Br4·2H2O (L = 3,14-diethyl-2,6,13,17-tetraazatricyclo[16.4.0.07,12]docosane, C22H44N4) has been determined using synchrotron radiation. The asymmetric unit contains one half of a [Cu(L)(H2O)2]2+ cation, one half of a [Cu(L)]2+ cation (both completed by crystallographic inversion symmetry), two bromide anions and one water solvent molecule. The CuII atom in the first complex exists in a tetragonally distorted octahedral environment with the four N atoms of the macrocyclic ligand in equatorial and two aqua ligands in axial positions, whereas the CuII atom in the second complex exists in a square-planar environment defined by the four nitrogen atoms of the macrocyclic ligand. The two macrocyclic rings adopt the most stable trans-III configuration with normal Cu—N bond lengths from 2.016 (3) to 2.055 (3) Å and an axial Cu—O bond length of 2.658 (4) Å. The crystal structure is stabilized by intermolecular hydrogen bonds involving the macrocycle N—H or C—H groups and the O—H groups of water molecules as donor groups, and the O atoms of water molecules and bromide anions as acceptor groups, giving rise to a one-dimensional network extending parallel to [100].

In the title complex, [Cu(C22H44N4)(H2O)2][Cu(C22H44N4)]Br4·2H2O, each of the two complex cations lies about an inversion center. The two macrocyclic rings adopt the most stable trans-III configuration. In the crystal, O—H⋯Br, N—H⋯Br, N—H⋯O and C—H⋯O hydrogen bonds connect the complex cations, bromide anions, semi-coordinating H2O ligands and water solvent mol­ecules, forming a one-dimensional network extending parallel [100]., The crystal structure of the new double CuII complex salt, [Cu(L)(H2O)2][Cu(L)]Br4·2H2O (L = 3,14-diethyl-2,6,13,17-tetra­aza­tri­cyclo­[16.4.0.07,12]docosane, C22H44N4) has been determined using synchrotron radiation. The asymmetric unit contains one half of a [Cu(L)(H2O)2]2+ cation, one half of a [Cu(L)]2+ cation (both completed by crystallographic inversion symmetry), two bromide anions and one water solvent mol­ecule. The CuII atom in the first complex exists in a tetra­gonally distorted octa­hedral environment with the four N atoms of the macrocyclic ligand in equatorial and two aqua ligands in axial positions, whereas the CuII atom in the second complex exists in a square-planar environment defined by the four nitro­gen atoms of the macrocyclic ligand. The two macrocyclic rings adopt the most stable trans-III configuration with normal Cu—N bond lengths from 2.016 (3) to 2.055 (3) Å and an axial Cu—O bond length of 2.658 (4) Å. The crystal structure is stabilized by inter­molecular hydrogen bonds involving the macrocycle N—H or C—H groups and the O—H groups of water mol­ecules as donor groups, and the O atoms of water mol­ecules and bromide anions as acceptor groups, giving rise to a one-dimensional network extending parallel to [100].

To study the Sr2+-ion selectivity of zeolite Y (Si/Al = 1.56) in binary solution with different Sr2+ and K+ concentration during exchange, two single-crystals of fully dehydrated, Sr2+- and K+-exchanged zeolites Y were prepared by the flow method using a mixed ion-exchange solution whose Sr(NO3)2:KNO3 mol ratios were 1:1 (crystal 1) and 1:100 (crystal 2), respectively, with a total concentration of 0.05 M, followed by vacuum dehydration at 723 K. Their crystal structures were determined by single-crystal synchrotron X-ray diffraction techniques in the cubic space group $$ Fd\bar{3}m $$, respectively, and were refined to the final error indices R1/wR2 = 0.0429/0.1437 and 0.0356/0.1239 for crystals 1 and 2, respectively. In the structure of |Sr28K19|[Si117Al75O384]-FAU (crystal 1), 28 Sr2+ ions per unit cell occupy four different crystallographically distinct sites; 15, 2, 2, and 9 are at sites I, I′, II′, and II, respectively, whereas, the K+ ions occupy only one site: 19 are at site II. In the structure of |Sr17K41|[Si117Al75O384]-FAU (crystal 2), 17 Sr2+ ions per unit cell occupy three equipoints; 10.5, 2, and 4.5 are at sites I, I′, and II, respectively. The residual 41 K+ ions per unit cell are found at four different sites; 8, 24, 3, and 6 are at sites I′, II, III′a, and III′b, respectively. The degrees of ion exchange are 74.7 and 45.3% for crystals 1 and 2, respectively. This result shows that the degree of Sr2+ exchange decreased sharply by decreasing the initial Sr2+ concentration and increasing the initial K+ concentration in the given ion-exchange solution.

Four single crystals of fully dehydrated and partially Zn2+-exchanged zeolites Y (Si/Al = 1.56) were prepared by the static ion-exchange method using a mixed ion-exchange solution in which Zn(NO3)2:NaCl mole ratios were 1:1 (crystal 1), 1:25 (crystal 2), 1:50 (crystal 3), and 1:100 (crystal 4), respectively, with a total concentration of 0.05 M, and followed by vacuum dehydration at 673 K. Their single-crystal structures were determined by single-crystal synchrotron X-ray diffraction techniques in the cubic space group Fd $$\bar {3}$$ m and refined to the final error indices R1/wR2 = 0.0459/0.1454, 0.0449/0.1283, 0.0427/0.1284, and 0.0486/0.1680, respectively. Their unit-cell formulas are |Zn25Na25|[Si117Al75O384]-FAU (crystal 1), |Zn19.5Na36|[Si117Al75O384]-FAU (crystal 2), |Zn19.5Na36|[Si117Al75O384]-FAU (crystal 3), and |Zn7Na61|[Si117Al75O384]-FAU (crystal 4), respectively. The degree of Zn2+ exchange decreases from 67 to 19% as the initial concentration of Zn2+ decrease and the initial concentration of Na+ increases in given ion-exchange solutions.

Seven single crystals of fully dehydrated Ni2+-exchanged zeolite Y (Si/Al = 1.56) were prepared via cation exchange of Na75-Y (|Na75|[Si117Al75O384]-FAU) by flowing 0.05 M aqueous solutions of Ni(NO3)2·6H2O (pH = 4.9, at 294 K) with various ion-exchange time. Their crystal structures were completely determined by single-crystal synchrotron X-ray diffraction techniques in the cubic space group Fd–3m at 100(1) K. In all seven structures, Ni2+ ions occupy sites I, I’, II, and sometimes II’ or a second II, or both, preferring site I; residual Na+ ions in crystals 1 and 2 are found at site III and/or a second III. The level of Ni2+ exchange monotonically increased from 75.2% to 89.6% (from 28.2(2) to 33.6(8) Ni2+ per unit cell) with increasing exchange time until 18 h. The dealumination of zeolite frameworks was observed in the center of sodalite cavities after 24 h, suggesting that this process occurs during ion-exchanges, or subsequent dehydration. H+ ions are present in all seven crystals for a charge balan...

To investigate the tendency of Mn(2+)-ion exchange into zeolite Y, four single crystals of fully dehydrated Mn2+, Na(+)-exchanged zeolite Y (Si/Al = 1.56) were prepared by the exchange of Na75-Y (INa75I[Si117Al75,O384]-FAU) with aqueous of various concentrations by Mn2+ and Na+ in a total 0.05 M for molar ratios of 1:1 (crystal 1), 1:25 (crystal 2), 1:50 (crystal 3), and 1:100 (crystal 4), respectively, followed by vacuum dehydration at 400 degrees C. Their single-crystal structures were determined by synchrotron X-ray diffraction techniques in the cubic space group Fd3(-)m and were refined to the final error indices R1/wR2 = 0.0440/0.1545, 0.0369/0.1153, 0.0373/0.1091, and 0.0506/0.1667, respectively. Their unit-cell formulas are approximately LMn33.5Na8I[Si117Al75O384]-FAU, IMn20.5Na34I[Si117Al75O384]-FAU, IMn20.5Na34I[Si117Al75O384]-FAU, and IMn16.5Na42I[Si117Al75O384]-FAU, respectively. The degree of Mn2+-ion exchange increases from 44.3% to 89.1% with increasing the initial Mn2+ concentrations as Na+ content and the unit cell constant of the zeolite framework decrease.

To study the tendency of Zn2+ exchange into zeolite A, two single-crystals of fully dehydrated Zn2+-and Na+-exchanged zeolite A were prepared by the static ion-exchange method using a mixed ion-exchange solution whose Zn(NO3)2:NaNO3 mol ratios were 1:4 (crystal 1) and 3:2 (crystal 2), respectively, with a total concentration of 0.05 M, followed by vacuum dehydration at 623 K. Their single-crystal structures and chemical compositions were determined by single-crystal synchrotron X-ray diffraction techniques and electron probe microanalysis. Their structures were refined to the final error indices R 1/wR 2 = 0.0678/0.2154 and 0.0619/0.1938 for crystals 1 and 2, respectively. In both structures, the 4 Zn2+ ions are located in sodalite unit, whereas, the remaining 4 Na+ ions are located in large cavity. Unit-cell formula of two single-crystal structures is approximately |Zn4Na4|[Si12Al12O48]-LTA. This work shows that the degree of Zn2+ exchange by increasing the initial Zn2+ concentration and decreasing the initial Na+ concentration in given ion-exchange solution does not differ significantly.

Three single crystals of fully dehydrated, largely Co2+-exchanged zeolites X and Y were prepared by the exchange of Na80-X (|Na80|[Si112Al80O384]-FAU, Si/Al = 1.40), Na75-Y (|Na75|[Si117Al75O384]-FAU, Si/Al = 1.56), and Na71-Y (|Na71|[Si121Al71O384]-FAU, Si/Al = 1.70) with aqueous streams 0.05 M in Co(NO3)2, pH = 5.1, at 294 K for 3 days. This was followed by vacuum dehydration at 673 K. Their crystal structures were determined by synchrotron X-ray diffraction techniques in the cubic space group Fd $$\overline{3}$$ m at 100(1) K. In all three crystals Co2+ ions occupy the 6-ring sites I, I’, and II; Na+ ions occupy sites II’ and II. The number of Co2+ ions exchanging into the zeolite was about 30 per unit cell for all three crystals. The number of residual Na+ ions, however, decreased sharply as Si/Al ratio increased, and the number of H+ ions co-exchanging into the zeolite decreased nearly to zero. Some dealumination of the zeolite framework was seen in the first crystal (initial Si/Al = 1.40).

A single crystal of excessively Ni2+-exchanged zeolite Y (FAU, Si/Al = 1.70) was prepared by exchange of |Na71|[Si121Al71O384]-FAU with an aqueous stream 0.05 M Ni(NO3)2 at 293 K and pH 4.9, followed by vacuum evacuation at room temperature and 1.3 × 10−4 Pa. Its crystal structure was determined by single-crystal synchrotron X-ray diffraction techniques in the cubic space group Fd $$\overline{ 3}$$ m and was refined to the final error indices R 1/wR 2 = 0.0554/0.1557 for |Ni24.7(NiOH)12.1(Ni2O(OH)2)4.8(Ni4AlO4)1.7Na17.0(H3O)6.9|[Si117Al75O384]-FAU. Crystal has about 53 Ni2+ ions per unit cell, indicating the uptake of excess Ni(OH)2, perhaps as NiOH+ ions. Some dealumination of the framework occurred during Ni2+ exchange. In this structure, Ni2+ ions occupy sites I, I′, II′, II, and III′. The residual Na+ ions are found at sites II′ and II. Due to the low pH of the Ni2+ exchange solution, some H3O+ ions are observed. Nonframework oxygen atoms as oxide and hydroxide ions and orthoaluminate coordinate to some of Ni2+ ions to give NiOH+, Ni2O(OH)2, and Ni4AlO4 3+ groups.

K for 6 h, 12 h, and 18 h, respectively, followed by vacuum dehydration at 673 K. Their single-crystal structures were determined by synchrotron X-ray diffraction techniques in the cubic space group Fd3m at 100(1) K. They were refined to the final error indices R1/wR2 = 0.0437/0.1165, 0.0450/0.1228, and 0.0469/0.1278, respectively. Their unit-cell formulas are |Co29.1Na11.8H5.0|[Si117Al75O384]-FAU, |Co29.8Na11.0H4.4|[Si117Al75O384]-FAU, and |Co30.3Na9.5H4.9|[Si117Al75O384]-FAU, respectively. In all three crystals, Co 2+ ions occupy sites I, I' and II; Na + ions are also at site II. The tendency of Co 2+ exchange slightly increases with increasing contact time as Na + content and the unit cell constant of the zeolite framework decrease.

The single-crystal structure of fully dehydrated zeolite Y (FAU, Si/Al = 1.56) Mn2+ exchanged by flow method, |Mn31(Mn4AlO4)H10|[Si117Al75O384]-FAU, was determined by single-crystal synchrotron X-ray diffraction techniques. It was refined to the final error indices R 1/wR 2 = 0.0692/0.2026 in the cubic space group $$Fd\overline{3}m$$ at 100(1) K. In this structure, 35 Mn2+ ions per unit cell are found at four crystallographic positions: 11 and 7 are at the centers of the double 6-rings (site I) and in the sodalite cavity opposite the double 6-rings (site I′), respectively. The remaining 4 and 13 are found at sites II′ (near 6-ring in the sodalite cavity) and II (near 6-ring in the supercage), respectively. Some dealumination of the zeolite framework occurred during Mn2+ exchange. The four non-framework oxygen atoms coordinate to a aluminate ion at the center of sodalite cavity (site U) and 4 Mn2+ ions at site II′ to give Mn4AlO4 3+. The 10 H+ ions are required for charge balance in fully dehydrated Mn2+-Y. The single-crystal structure of fully dehydrated, partially dealuminated, and Mn2+-exchanged zeolite Y (FAU (Si/Al = 1.56) was determined by single-crystal synchrotron X-ray diffraction techniques.

A single crystal of fully dehydrated, largely Rb+-exchanged zeolite Y, |Rb59Na16|[Si117Al75O384]-FAU (Si/Al = 1.56), prepared by exchange of |Na75|[Si117Al75O384]-FAU with an aqueous stream 0.1 M RbOH at 293 K, followed by vacuum dehydration at 673 K and at 1 × 10−6 Torr. Its crystal structure was determined by single-crystal synchrotron X-ray diffraction techniques in the cubic space group Fd $$\overline{3}$$ m and was refined to the final error indices R 1/wR 2 = 0.0392/0.1189. In the structure of |Rb59Na16|[Si117Al75O384]-FAU, about 59 Rb+ ions per unit cell occupy five different equipoints; 9 are at site I, 9 at site I′, 3 at site II′, 28 at site II, and the remaining 10 are at site III, preferring II. The residual 16 Na+ ions occupy three equipoints; 5 are at site I′, 3 at site II, and 8 are at site III. These Rb+ and Na+ ions filled full from hexagonal prism to supercage. This work achieved the highest level of Rb+-exchange (ca. 81 %) in the single-crystal structure of zeolite Y by conventional method using aqueous solution at room temperature. The distributions of Rb+ and Na+ ions in this structure, as compared to fully dehydrated partially Rb+-exchanged zeolite X, are different due to local Si/Al order among the T atoms. The single-crystal structure of fully dehydrated, largely Rb+-exchanged zeolite Y, |Rb59Na16|[Si117Al75O384]-FAU (Si/Al = 1.56), was determined by single-crystal synchrotron X-ray diffraction techniques.

A single crystal of excessively Pb2+-exchanged zeolite Y (|Pb 15.5 2+ (Pb4O4(Pb 16/19 2+ Pb 3/19 4+ )4)4.75|[Si117Al75O384]-FAU) was prepared by exchange of Na–Y (|Na75|[Si117Al75O384]-FAU, Si/Al = 1.56) with an aqueous stream 0.05 M Pb(C2H3O2)2 at 294 K, followed by vacuum dehydration at 1 × 10−6 Torr and 693 K. Its structure was determined at 100 K, by X-ray diffraction techniques in the cubic space group Fd $$ \overline{3} $$ m and was refined to the final error indices R 1/wR 2 = 0.0639/0.1323. About 53.5 Pbn+ ions per unit cell occupy three different equipoints; 26 are at site I′, 19 are at site II, and the remaining 8.5 are at another site II. Three Pb4+ ions at some of the positions must have higher oxidation states due to elevated dehydration temperature; Pb(IIa) is supposed to coexist with Pb2+ and Pb4+ ions assuming the charge balance of the zeolite framework. A distorted Pb4O4 cube, alternating Pb2+ at Pb(I′) and O2− at O(5), coordinates with four Pb2+ and/or Pb4+ ions through its oxygen atoms to give a [Pb 4 2+ O 4 2− (Pb 16/19 2+ Pb 3/19 4+ )4]176/19+ cluster in 4.75 of eight sodalite cavities per unit cell in zeolite Y.

The crystal structure of partially dehydrated fully Zn 2+ -exchanged zeolite Y was determined by X-ray diffraction techniques in the cubic space group Fd3m at 294(1) K and refined to the final error indices R₁/wR₂ = 0.035/0.119 for |Zn 35.5 (H₂O) 13 |[Si 121 Al 71 O 384 ]-FAU. About 35.5 Zn 2+ ions per unit cell are found at six distinct positions; sites I, I’, a second I’, II’, II, and a second II. In sodalite cavities, the 11 water molecules coordinate to Zn(I’b) and/or Zn(II’) ions; each of two H₂O bonds to a Zn(IIb) in supercages. Two different Zn 2+ positions near 6-oxygen ring are due to their Si-Al ordering in tetrahedral site by Si/Al ratio leading to the different kinds of 6-rings.

The crystal structures of zeolite Y Ni2+ exchanged at pH 4.9, fully dehydrated (|Ni29.7(Ni4AlO4)1.1H12.3|[Si117Al75O384]-FAU) and partially dehydrated (|Ni14.1(NiOH2)16.4(Ni4AlO4)1.1(H3O)9.6|[Si117Al75O384]-FAU), were determined by single-crystal synchrotron X-ray diffraction techniques. They were refined to the final error indices R1/wR2 = 0.044/0.115 and 0.052/0.153, respectively, in the cubic space group Fd3m. Some dealumination of the zeolite framework occurred during Ni2+ exchange. In the fully dehydrated structure, Ni2+ ions primarily occupy sites I and II, with additional Ni2+ ions at site I′, site II′, and a second site II. In the partially dehydrated structure, Ni2+ occupies six different sites: I, I′, a second site I′, II, a second site II, and III′. Because of the low pH of the Ni2+ exchange solution, some H3O+ ions are observed in partially dehydrated Ni2+–Y; correspondingly, some H+ ions are required for charge balance in fully dehydrated Ni2+–Y. The nonframework oxygen atoms in water and or...

Two single crystals of fully dehydrated, mostly Cu2+-exchanged zeolite Y were prepared by the exchange of Na75–Y (|Na75|[Si117Al75O384]-FAU, Si/Al = 1.56) with an aqueous stream 0.05 M in Cu(NO3)2, pH = 4.2, at 294 K for 18 and 24 h, respectively, followed by vacuum dehydration at 673 K and 1 × 10–6 Torr. Their crystal structures were determined by synchrotron X-ray diffraction techniques in the cubic space group Fd3m at 100(1) K and were refined to the final error indices R1/wR2 = 0.050/0.165 and 0.050/0.163, respectively, for |Cu32.6Na5.3H4.5|[Si117Al75O384]-FAU and |Cu33.0Na3.9H5.1|[Si117Al75O384]-FAU, respectively. Cu2+ ions occupy the 6-ring sites I′ and II, preferring I′; Na+ ions also occupy sites I′ and II; neither site is filled. All Cu2+ ions in these structures coordinate not only to three trigonally arranged oxygen atoms of their 6-rings, but also to a fourth oxygen atom of those 6-rings to achieve planar, severely distorted square, 4-coordination. This result is in agreement with DFT calcula...

A single crystal of zeolite Y, 0.30 mm in diameter, fully exchanged with Mn2+ and fully dehydrated, was treated with zeolitically dry toluene at 298(1) K and a pressure of 1.3 × 10–4 Pa and evacuated for 2 h. The crystal structure, |Mn37.5(C7H8)17|[Si117Al75O384]-FAU (a = 24.5923(1) A), was determined by synchrotron X-ray diffraction techniques in the space group Fd3m at 100(1) K and was refined to the final error indices R1 = 0.083 and wR2= 0.230. Mn2+ ions occupy sites I, I′, II′, and II with occupancies at 14, 4, 2.5, and 17, respectively. The 17 Mn2+ ions per unit cell at site II each coordinates to three framework oxygen atoms at 2.213(6) A and extends into the supercage by 0.63 A from their plane. Each of these Mn2+ ions also interacts facially with a toluene molecule (Mn2+–toluene center = 2.62 A). The methyl group is somewhat off the plane of the ring, indicative of a net repulsive interaction with the zeolite framework.

Three single crystals of zeolite Y, each 0.3 mm in diameter, fully exchanged with Mn2+ and fully dehydrated, were treated with zeolitically dry o-, m-, and p-xylene, respectively, at 297(1) K, followed by evacuation. Their crystal structures were determined by synchrotron X-ray diffraction techniques in the space group Fd3m at 100(1) K and were refined using all intensities to the final error indices R1/wR2 = 0.056/0.160, 0.080/0.217, and 0.066/0.177, respectively. In each structure, Mn2+ ions occupy sites I, I′, II′, and II. In each structure, 18 Mn2+ ions per unit cell at site II (on the 3-fold axes of the single 6-rings) each extend 0.63, 0.68, and 0.67 A into the supercage to coordinate facially to an o-, m-, and p-xylene molecule, respectively. The corresponding distances from Mn2+ to the centers of the xylene rings are 2.67, 2.65, and 2.63 A. The methyl groups are all somewhat off the planes of their rings, indicative of a net repulsive interaction with oxygen atoms of the zeolite framework. The h...

The polyatomic tetrahydroxytetraindium(III) cations, In4(OH)48+, have been synthesized in 94% of the sodalite cavities of zeolite Y (FAU, Si/Al = 1.69). In−Y (|In57.8[In5]1.8|[Si121Al71O384]−FAU or In66.8−Y) was prepared by the oxidative solid state ion exchange (OSSIE) method from In0 and single crystals of Tl−Y under anhydrous conditions at 623 K. One of these was exposed to the atmosphere and then zeolitically dry oxygen, both at 623 K, to give In−Y[In4(OH)4] (|In7.6[In4(OH)4]7.5[In(OH)2]2.0|[Si121Al71O384]−FAU or In39.6(OH)34.0−Y). The structures of In−Y and In−Y[In4(OH)4] were determined by single crystal crystallography with synchrotron X-radiation. They were refined in the space group Fd3m (a = 24.863(1) and 24.518(1) A) with all unique data to the final error indices R1 = 0.050 and 0.057 for the 1110 and 1037 reflections for which Fo > 4σ(Fo), respectively. The In in In−Y is mostly In+; some In57+ clusters are present in sodalite cavities. Upon oxidation in the presence of water, 41% of the In ex...

A single crystal of zeolite Y, |Na71|[Si121Al71O384]-FAU, was ion exchanged to generate |(NH4)38Na33|[Si121Al71O384]-FAU. This was then vacuum dehydrated at 673 K, and, without re-exposure to the atmosphere, its structure was determined crystallographically using synchrotron X-radiation in the cubic space group $$ Fd\bar{3} $$ m at 294 K. It was refined to the final error index R 1 = 0.0532 with 522 reflections for which F o > 4σ(F o). The composition (best integers) is determined to be |Na33H26(Al5O4)|[Si126Al66O384]-FAU which means full dehydration, deamination, and dealumination were achieved. The 33 Na+ ions per unit cell were found at two crystallographically distinct positions: nine at site I (in the centers of the D6Rs) and 24 at site II (in supercages opposite S6Rs). The 2.5 sodalite units contained a dimeric tetrahedral aluminate cation (Al–O = 1.40(8) and 1.60(8) A) at its center. Each [Al5O4]7+ cation coordinates to framework oxygen of D6Rs with tetrahedral manner. This work demonstrates that it is possible to obtain large amount of dealuminated species within the H-Y zeolite framework which should enhance the acidity of adjacent sites for higher catalytic activity.

Crystal structure determinations on Cu(II) and Zn(II) complexes of tridentate and quadridentate azetidine derivatives show the ligands to be facultative for square-pyramidal and trigonal bipyramidal coordination geometries. While various contributions to the chirality of the complexes are possible, single diastereoisomeric forms (as enantiomer mixtures) have been isolated in all cases in the solid state. Analysis of lattice interactions indicates that H-bonding and aromatic stacking interactions are generally important.

Single crystals of fully dehydrated and fully Ca 2+ -exchanged zeolites A (|Ca 6 |[Si 12 Al 12 O 48 ]-LTA) and X (|Ca 46 | [Si 100 Al 92 O 384 ]-FAU) were brought into contact with Te in fine pyrex capillaries at 623 K and 673 K, respectively, for 5 days. Crystal structures of Te-sorbed Ca 2+ -exchanged zeolites A and X have been determined by single-crystal X-ray diffraction techniques at 294 K in the cubic space group Pm3m (a = 12.288(2) A) and Fd 3 (a = 25.012(1) A), respectively. The crystal structures of pale red-brown |Ca 6 Te 3 |[Si 12 A 12 O 48 ]-LTA and black coloured |Ca 46 Te 8 | [Si 100 Al 92 O 384 ]-FAU have been refined to the final error indices of R 1 /wR 2 = 0.1096/0.2768 and R 1 /wR 2 = 0.1054/ 0.2979 with 204 and 282 reflections for which F o > 4σ(F o ), respectively. In the structure of |Ca 6 Te 31 |[Si 12 Al 12 O 48 ]-LTA, 6 Ca 2+ ions per unit cell were found at one crystallographic positions, on 3-fold axes equipoints of opposite 6-rings. In |Ca 46 Te 8 |[Si 100 Al 92 O 384 ]-FAU, 46 Ca 2+ ions per unit cell were found at four crystallographically distinct positions: 3 Ca 2+ ions at Ca(1) fill the 16 equivalent positions of site I, 21 Ca 2+ ions at Ca(2) fill the 32 equivalent positions of site I', 10 and 12 Ca 2+ ions at Ca(3) and Ca(4), respectively, fill the 32 equivalent positions of site II. The Te clusters are stabilized by interaction with cations and framework oxygen. In sodalite units, Te-Te distances of 2.86(10) and 2.69(4) A in zeolites A and X, respectively exhibited strong covalent properties due to their interaction with Ca 2+ ions. On the other hand, in large cavity and supercage, those of 2.99(3) and 2.76(11) A in zeolites A and X, respectively, showed ionic properties because alternative ionic interaction was formed through framework oxygen at one end and Ca 2+ cations at the other end.

The single-crystal structure of largely ammonium-exchanged zeolite Y dehydrated at room temperature (293 K) and 1 x 10(-6) Torr. has been determined using synchrotron X-radiation in the cubic space group Fd (3) over barm (a 24.9639(2) angstrom) at 294 K. The structure was refined to the final error index R-1 = 0.0429 with 926 reflections where F-o > 4 sigma(F-o); the composition (best integers) was identified as vertical bar(NH4)(60)Na-11 vertical bar[Si121Al71O384]-FAU. The 11 Na+ ions per unit cell were found at three different crystallographic sites and 60 NH4+ ions were distributed over three sites. The 3 Na+ ions were located at site I, the center of the hexagonal prism (Na-O = 2.842(5) angstrom and O-Na-O = 85.98(12)degrees). The 4 Na+ and 22 NH4+ ions were Pound at site I' in the sodalite cavity opposite the double 6-rings, respectively (Na-O = 2.53(13) angstrom, O-Na-O = 99.9(7)degrees, N-O = 2.762(11) angstrom, and O-N-O = 89.1(5)degrees). About 4 Na+ ions occupied site II (Na-O = 2.40(4) angstrom and O-Na-O = 108.9(3)degrees) and 29 NH4+ ions occupy site II (N-O = 2.824(9) angstrom and O-N-O = 87.3(3)degrees) opposite to the single 6-rings in the supercage. The remaining 9 NH4+ ions were distributed over site III' (N-O = 2.55(3), 2.725(13) angstrom and O-N-O = 94.1(13), 62.16(15), 155.7(14)degrees).

The tauto-merism (Scheme 1) of these ligands as well as the wellknown tendency of sulfur donors to act as bridging ligandsallows various structural possibilities for the correspondingmetal complexes. As part of our studies on the coordination chemistry of d-block metal complexes with schiff base ligands, we haveearlier reported the synthesis and spectroscopic and electro-chemical properties for the dioxomolybdenum(VI) com-plexes, such as [MoO

Department of Applied Chemistry, Andong National University, Andong, Gyeongbuk 760-749, Korea(Received May 20, 2008)주제어: Dioxomolybdenum(VI) 착물, Schiff 염기, 4,4'-Bipyridine, 4,4'-Dipyridyldioxide, 결정구조Keywords: Dioxomolybdenum(VI) complexes, Schiff-base ligands, 4,4'-Bipyridine ,4,4'-Dipyridyldioxide, Crystal structure

However, to our knowledge, trivalentcobalt complex with bicarbonate as counter ionin the formula is not known up to now. Thereby,we report here the preparation and structure of 1.EXPERIMENTALSynthesis. All chemicals were commerciallypurchased and used without further purification.Elemental analyses (C, H, N) were performed ona Carlo Erba EA-1106 Elemental Analyzer. IRspectrum was recorded in the range 400-4000 cm

Large colorless single crystals of faujasite-type zeolite with diameters up to 200 /an have been synthesized from gels with the composition of 3.58SiO 2 :2.08NaAlO 2 :7.59NaOH:455H 2 O:5.06TEA:1.23TCl. Two of these, colorless octahedron about 200 μm in cross-section have been treated with aqueous 0.1 M TlC 2 H 3 O 2 and KNO 3 in order to prepare Tl + - and K + -exchanged faujasite-type zeolites, respectively, and then determined the Si/Al ratio of the zeolite framework. The crystal structures of |Tl 71 |[Si 121 Al 71 O 384 ]-FAU and |K 53 Na 18 |[Si 121 Al 71 O 384 ]-FAU per unit cell, a = 24.9463(2) and 24.9211(16) A, respectively, dehydrated at 673 K and 1 x 10 -6 Torr, have been determined by single-crystal X-ray diffraction techniques in the cubic space group Fd3 m at 294 K. The two single-crystal structures were refined using all intensities to the final error indices (using only the 905 and 429 reflections for which F o > 4σ(F o )) R 1 /R 2 = 0.059/0.153 and 0.066/0.290, respectively. In the structure of fully Tl + -exchanged faujasite-type zeolite, 71 Tl + ions per unit cell are located at four different crystallographic sites. Twenty-nine Tl + ions fill site I' in the sodalite cavities on 3-fold axes opposite double 6-rings (Tl-O = 2.631(12) A and O-Tl-O = 93.8(4)°). Another 31 Tl + ions fill site II opposite single 6-rings in the supercage (Tl-O = 2.782(12) A and O-Tl-O = 87.9(4)°). About 3 Tl + ions are found at site III in the supercage (Tl-O = 2.91(6) and 3.44(3) A), and the remaining 8 occupy another site III (Tl-O = 2.49(5) and 3.06(3) A). In the structure of partially K + -exchanged faujasite-type zeolite, 53 K + ions per unit cell are found at five different crystallographic sites and 18 Na + ions per unit cell are found at two different crystallographic sites. The 4 K + ions are located at site I, the center of the hexagonal prism (K-O = 2.796(8) A and O-K-O = 89.0(3)°). The 10 K + ions are found at site I' in the sodalite cavity (K-O = 2.570(19) A and O-KO = 99.4(9)°). Twenty-two K + ions are found at site II in the supercage (K-O = 2.711(9) A and O-K-O = 94.7(3)°). The 5 K + ions are found at site III deep in the supercage (K-O = 2.90(5) and 3.36(3) A), and 12 K + ions are found at another site III' (K-O = 2.55(3) and 2.968(18) A). Twelve Na + ions also lie at site I' (Na-O = 2.292(10) and O-Na-O = 117.5(5)°). The 6 Na + ions are found at site II in the supercage (Na-O = 2.390(17) A and O-Na-O = 113.1(11)°). The Si/Al ratio of synthetic faujasite-type zeolite is 1.70 determined by the occupations of cations, 71, in two single-crystal structures.

A new polyoxomolybdenum compound [Mo 4 O 12 (2,2′-bpy) 3 ] n ( 1 ) (2,2′-bpy = 2,2′-bipyridine) has been hydrothermally synthesized and characterized by elemental analysis, IR spectroscopy, TG analysis, and single crystal X-ray diffraction. The solid state structure is a 1D chain with a repeat unit of three corner-sharing {MoO 4 N 2 } octahedra and one {MoO 4 } tetrahedron.

Summary Large single crystals of zeolite X (Si/Al = 1.41) weresuccessfully prepared from gels with the composition2.40SiO 2 : 2.00NaAlO 2 : 7.52NaOH : 454H 2 O : 5.00TEAand the structure of fully K + -exchanged zeolite X wasdetermined by single-crystal X-ray diffraction methods. Thesynthetic produts are consisted of the large transparentcrystals of faujasite-type zeolite with diameters up to ca . 200μm and the translucent polycrystalline spheres of gismon-dine. In the SEM-EDS anaysis, the Si/Al ratio of thesynthetic faujasite-type zeolite is 1.41 which is well con- Figure 5 . A stereoview of a representative supercage in dehydrated |K 80 |[Si 112 Al 80 O 384 ]-FAU. See the caption to Figure 3 for other details. Table 6 . Distribution of K + ions over sites in |K 92 |[Si 100 Al 92 O 384 ]-FAU a,b and |K 80 |[Si 112 Al 80 O 384 ]-FAU c Site I I' II III III'Maximum occupancy 16 32 32 48 96Position K(Ia) K(Ib) K(I'a) K(I'b) K(I'c) K(II) K(III) K(III'a) K(III'b) K(III'c)Structure Occupancies|K

The structure of [CrF(2)([15]aneN(4))]ClO(4).H(2)O ([15]aneN(4)=1,4,8,12-tetraazacyclopentadecane) has been determined by a single-crystal X-ray diffraction study at 173 K. The complex crystallizes in the space group P1- of the triclinic system with two mononuclear formula units in a cell of dimensions a=9.6117(7) A, b=10.2882(7) A, c=11.0001(7) A and alpha=99.7570(10) degrees, beta=105.6080(10) degrees and gamma=113.7130(10) degrees. The complex cation unit has its central Cr atom in an octahedral coordination with four nitrogen atoms and two fluorine atoms in a trans position. Three six-membered and one five-membered chelate rings of the [15]aneN(4) ligand are in a chair-twist(skew)-chair-gauche conformation sequence. The gauche five-membered ring is disordered with the twist six-membered ring opposite. The four H atoms in the chiral N atoms have the trans-II (CTCg) type configuration. The mean Cr-N and Cr-F bonds are 2.095(2) and 1.8752(13) A, respectively. The IR and visible spectral properties are consistent with the result of X-ray crystallography. The resolved band maxima of the electronic d-d spectrum are fitted with secular determinant for quartet state energy of d(3) configuration in tetragonal field including configurational but neglecting spin-orbit coupling. It is confirmed that the fluoride has strong sigma- and pi-donor properties toward the chromium(III) ion and the nitrogen atoms of the [15]aneN(4) ligand also have a strong sigma-donor character.

The crystal structure of K71-Y (FAU), K71Si121Al71O384 per unit cell, a = 24.9976(7) A, dehydrated at 653 K and 8 × 10−6 Torr, has been determined by single-crystal X-ray diffraction techniques in the cubic space group Fd 3 ¯ m at 294 K. The structure was refined using all intensities to the final error indices (using only the 695 reflections for which Fo > 4σ(Fo)) R1 = 0.045 (based on F) and R2 = 0.136 (based on F2). About 71 K+ ions per unit cell are found at an unusually large number of crystallographically distinct positions, eight. They exhibit the same degree of cation crowding seen in K92-X (FAU) as K+ ions continue to crowd into sites I and I′. Six K+ ions are at the centers of double 6-rings (D6Rs, site I; K–O = 2.733(5) A and O–K–O (octahedral) = 89.90(14)° and 90.10(14)°). Five additional K+ ions are near site I (K–O = 2.530(11) and 2.972(15) A); each is pushed off center by a K+ ion at a site-I′ position. Two site-I′ positions (in the sodalite cavities opposite D6Rs) are occupied by ten and five K+ ions, respectively, per unit cell; these K+ ions are recessed 1.30 A and 1.68 A into the sodalite cavities from their 3-oxygen planes (K–O = 2.581(15) and 2.69(3) A, and O–K–O = 96.9(7)° and 84.9(14)°, respectively). These five site-I′ K+ ions push the five site-I K+ ions off center (K+ ⋯ K+ = 3.65(4) A), and, in turn, are themselves pushed deeper into the sodalite cavities. Nearly filling site II in the supercages are 30.3(3) K+ ions, each of which extends 1.36 A into the supercage from its 3-oxygen plane (K–O = 2.688(4) A and O–K–O = 96.86(13)°). The 9.4(4) K+ ions at site III in the supercages each lie opposite the central ring of a triple 4-ring (K–O = 2.894(11) A twice and O–K–O = 81.2(4)°). The remaining 2.0(7) and 1.5(6) K+ ions occupy two sites III′ near triple 4-rings in the supercage (K–O = 2.41(10), 2.89(5), 2.57(8), and 2.97(4) A). K71-Y has 20 fewer K+ ions at III′ sites than K92-X; other much smaller occupancy differences are seen.

Ag 4 Br 4 nanoclusters have been synthesized in about 75% of the sodalite cavities of fully K + -exchanged zeolite A (LTA). An additional KBr molecule is retained in each large cavity as part of a near square-planar K 4 Br 3 + cation. A single crystal of Ag 1 2 -A, prepared by the dynamic ion-exchange of Na 1 2 -A with aqueous 0.05 M AgNO 3 and washed with CH 3 OH, was placed in a stream of flowing 0.05 M KBr in CH 3 OH for two days. The crystal structure of the product (K9(K4Br)Si 1 2 Al 1 2 O 4 8 .0.75Ag 4 Br 4 , a = 12.186(1) A) was determined at 294 K by single-crystal X-ray diffraction in the space group Pm3 m. It was refined with all measured reflections to the final error index R 1 = 0.080 for the 99 reflections for which F o > 4σ(F o ). The thirteen K + ions per unit cell are found at three crystallographically distinct positions: eight K + ions in the large cavity fill the six-ring site, three K' ions fill the eight-rings, and two K' ions are opposite four-rings in the large cavity. One bromide ion per unit cell lies opposite a four-ring in the large cavity, held there by two eight-ring and two six-ring K + ions (K 4 Br 3 + ). Three Ag' and three Br ions per unit cell are found on 3-fold axes in the sodalite unit, indicating the formation of nano-sized Ag 4 Br 4 clusters (interpenetrating tetrahedra; symmetry T d ; diameter ca. 7.9 A) in 75% of the sodalite units. Each cluster (Ag-Br = 2.93(3) A) is held in place by the coordination of its four Ag + ions to the zeolite framework (each Ag' cation is 2.52(3) A from three six-ring oxygens) and by the coordination of its four Br ions to K' ions through six-rings (Br-K = 3.00(4) A).

Ag 4 I 4 nanoclusters have been synthesized in half of the sodalite cavities of fully K + -exchanged zeolite A. An additional KI molecule is retained in each large cavity as part of a near square planar K 4 I 3 + cation. A single crystal of Ag 1 2 -A, prepared by the dynamic ion-exchange of Na 1 2 -A (LTA) with aqueous 0.05 M AgNO 3 and washed with CH 3 OH, was placed in a stream of flowing 0.05 M KI in CH 3 OH at 294 K for 2 days. The crystal structure of the product, K 9 Si 1 2 Al 1 2 O 4 8 .(Ag 4 I 4 ) 0 . 5 .K 4 I 3 + , a = 12.290(1) A, was determined by single-crystal X-ray diffraction in the cubic space group Pm3m. It was refined with all measured reflections to the final error index R 1 = 0.077 (based on the 264 reflections for which F o > 4σ(F o )). The thirteen K + ions per unit cell are found at three crystallographically distinct positions: eight K + ions in the large cavity fill the 6-ring site, three K + ions fill the 8-rings, and two K + ions are opposite 4-rings in the large cavity. One iodide ion per unit cell lies opposite a 4-ring in the large cavity, held there by two 8-ring and the two 6-ring K + ions (K 4 I 3 + ). Two Ag + and two I - ions per unit cell are found on 3-fold axes in the sodalite cavity, indicating the formation of Age clusters (interpenetrating tetrahedra; symmetry T d ; diameter ca. 8.0 A) in half of the sodalite units. Each cluster (Ag-I = 2.97(2) A) is held in place by the coordination of its four Ag + ions to the zeolite framework (each Ag + cation is 2.48(1) A from three 6-ring oxygens) and by the coordination of its four I - ions to large-cavity K + ions through 6-rings (I-K = 2.72(6) A).

A new spiroxazine 4 was found to be photochromic and thermochromic both in solution and in the crystalline state. X-ray crystallography was used to determine that the molecules of the spiroxazine were arranged in a monoclinic (C2) crystallographic system. Intermolecular hydrogen bonds, together with interlayer, aromatic π–π stacking interactions, stabilize the molecular conformation and packing in the crystal structure.

A spatially ordered quantum dot array of cationic indium nanoclusters has been synthesized in a single crystal of zeolite X. A single crystal of fully dehydrated and fully indium-exchanged zeolite X (ca. In87Si100Al92O384, In87−X) was exposed to 0.5 atm of H2S for 12 h at 673 K. After it was evacuated at temperature and cooled to 294 K, the crystal structure of the product (ca. In66Si100Al92O384, In66−X, a = 24.942(4) A) was determined by single crystal X-ray diffraction techniques in the cubic space group Fd3m. It was refined with all measured reflections to the final error index R1 = 0.058 for the 754 reflections with Fo > 4σ(Fo). X-ray photoelectron spectroscopy experiments confirmed the existence of both atomic and cationic indiums inside the single crystal. The 66 indium atoms or ions per unit cell were found at four crystallographically distinct positions, all on 3-fold axes. Eight In atoms at the sodalite unit centers and 32 Inca.2+ ions nearby (Inca.2+−In0 = 2.683(1) A), both filling their crysta...

A novel spiroxazine containing a mesogenic group has been prepared. The colourless spiroxazine exhibit photochromism through ring opening of the oxazine ring. The crystal structure was determined by X-ray crystallography and the crystal was found to exist in the triclinic space group P1 (No. 1).

Four single crystals of fully dehydrated, fully indium-exchanged zeolite A (Inca. 10−Si12Al12O48 or Inca. 10-A, colorless) were exposed to 0.5 atm of H2S for 3 h at 298, 373, 423, and 573 K for crystals 1 to 4, respectively. After evacuation at temperature followed by cooling to 294(2) K, the crystals were red, brown, yellow, and yellow, respectively. Their structures were determined by single-crystal X-ray diffraction techniques in the cubic space group Pm3m at 294(2) K (a = 12.083(3), 12.076(2), 12.094(2), and 12.094(2) A; R1 = 0.069, 0.063, 0.065, and 0.060; R2 = 0.062, 0.058, 0.064, and 0.060 for crystals 1 to 4, respectively). The structures differ in the degree of sorption and/or reaction with H2S. Crystal 1 (In9.5H0.5−A(InSH)0.5(H2S)2.5) may be viewed as being an equimolar mixture of two kinds of unit cells with compositions In9−A(H2S)3 and In10H−A(InSH)(H2S)2. Unit cell 1 contains three H2S molecules stabilized as [(In)2(H2S)3]2+ in the large cavity and a tetrahedral (In5)n+ cluster in the sodali...

Salt occlusion in zeolites is a unique phenomenon and plays an important role in solid and molten state reactions. To elucidate its mechanism, the NH 4 NO 3 occlusion was studied with various zeolites that exhibit diversity in pore shape (channel and cavity), window size, and composition and charge of framework. We also attempted to classify NH 4 NO 3 introduced into zeolite pores by characterizing their properties such as stability against washing with water, thermal behavior, and spectroscopic characteristics. Based on the geometric consideration between zeolite pores and salts, the salts introduced into zeolite pores could be classified as `dispersed', `occluded', and `trapped' salts. This classification was based on their stability against washing with water. Occluded NH 4 NO 3 salts were present in the pores of zeolites such as AlPO 4 -18, Na-P1 and 4A, while dispersed ones were observed in those of zeolites such as ZSM-5 and 13X. Framework charge was not essential in salt occlusion, although it affected the occluded amount and stability of occluded NH 4 NO 3 . It is clear from these results that the requirement for salt occlusion is the proper size fit between the window size of zeolite pore and the size of each ion pair of salt. Occluded salts were stabilized through geometric fit and/or electrostatic interactions with negatively charged frameworks that led to increase in their stabilities against washing with water and thermal treatment. Therefore, the geometric relationship of zeolite pore to salt plays more crucial role in salt occlusion than framework charge.

Fully indium-exchanged zeolite X has been prepared by solvent-free redox ion-exchange of fully dehydrated fully Tl+-exchanged zeolite X with In metal at 350 °C. Electron-probe microanalysis and sin...

The positions of Xe atoms encapsulated in the cavities of fully dehydrated zeolite A of unit-cell composition Cs3Na8HSi12Al12O48 (Cs3-A) have been determined. Cs3-A was exposed to 255 atm of xenon at 400 °C for 7 days, followed by cooling at pressure to encapsulate Xe atoms; a second crystal was treated similarly at 450 atm, and a third at 1020 atm. The resulting crystal structures of Cs3-A(2.5Xe) (crystal 1, a = 12.245(2) A, R1 = 0.056, R2 = 0.059), Cs3-A(4.5Xe) (crystal 2, a = 12.258(2) A, R1 = 0.061, R2 = 0.058), and Cs3-A(5.25Xe) (crystal 3, a = 12.236(2) A, R1 = 0.061, R2 = 0.057) were determined by single-crystal X-ray diffraction techniques in the cubic space group Pm3m at 21(1) °C and 1 atm. The approximately 2.5, 4.5, and 5.25 Xe atoms per unit cell, respectively, are distributed over three crystallographically distinct positions. At the center of each sodalite unit in crystals 1, 2, and 3, respectively, are 0.5, 0.75, and 0.75 Xe atoms at Xe(1); in addition, off center in crystal 3 are 0.25 Xe a...

An intermolecular charge–transfer (CT) complex was obtained from 2,3-diaminonaphthalene as donor with chloranil as acceptor. The crystal structure, as shown by an X-ray analysis, was composed of the donor and acceptor alternatively. The component molecules are stacked on top of each other to form a column along the a-axis. ©

The crystal structure of a new dithiosquarylium dye (DTSQ), viz, 2,4-bis(1,3,3-trimethyl-2-indolinylidenemethyl) cyclobutenediylium-1,3-dithiolate, has been determined by X-ray crystallography. A crystal was grown from chloroform/ethylacetate (8:1/v:v) and found to exist in the monoclinic space group P2 1 /n (no. 14). The molecule is roughly planar and adopts the trans conformation.

In the title compound, [Cr(ONO)(2)(cyclam)]NO(2) (cyclam is 1,4,8,11-tetraazacyclotetradecane, C(10)H(24)N(2)), the complex cation is located on a twofold symmetry axis. The central Cr atom has a distorted octahedral coordination, involving two Cr-O bonds, with the monodentate nitrite O atoms adopting a cis configuration, and four Cr-N bonds. The mean Cr-N and Cr-O distances are 2.0895 (14) and 1.9698 (14) A.

The crystal structure and the distribution and coordination geometry of Mg2+ ions in the title zeolite are determined by single crystal XRD.

The positions of PbI 2 molecule synthesized into the molecular-dimensioned cavities of |K 6 (Pb 4 I 2 )(PbI 2 ) 0.67 -(H 2 O) 2 |[Si 12 Al 12 O 48 ]-LTA have been determined. A single crystal of |Pb 6 |[Si 12 Al 12 O 48 ]-LTA, prepared by the dynamic ion-exchange of |Na 12 |Si 12 Al 12 O 48 -LTA with aqueous 0.05 M Pb(NO 3 ) 2 and washed with deionized water, was placed in a stream of flowing aqueous 0.05 M KI at 294 K for three days. The resulting crystal structure of the product (|K 6 (Pb 4 I 2 )(PbI 2 ) 0.67 (H 2 O) 2 |[Si 12 Al 12 O 48 ]-LTA, a = 12.353(1) A) was determined at 294 K by single-crystal X-ray diffraction in the space group Pm 3m. It was refined with all measured reflections to the final error index R 1 = 0.062 for 623 reflections which F o > 4σ(F o ). 4.67 Pb 2+ and six K + ions per unit cell are found at three crystallographically distinct positions: 3.67 Pb 2+ and three K + ions on the 3-fold axes opposite six-rings in the large cavity, three K + ions off the plane of the eight-rings, and the remaining one Pb 2+ ion lies opposite four-ring in the large cavity. 0.67 Pb 2+ ions and 1.34 I - ions per unit cell are found in the sodalite units, indicating the formation of a PbI 2 molecule in 67% of the sodalite units. Each PbI 2 (Pb-I = 3.392(7) A) is held in place by the coordination of its one Pb 2+ ion to the zeolite framework (a Pb 2+ cation is 0.74 A from a six-ring oxygens) and by the coordination of its two I - ions to K + ions through six-rings (I-K = 3.63(4) A). Two additional I - ions per unit cell are found opposite a four-ring in the large cavity and form Pb 2 K 2 I 5+ and PbK 2 I 3+ moieties, respectively, and two water molecules per unit cell are also found on the 3-fold axes in the large cavity.

Ag 4 I 4 nanoclusters have been synthesized in half of the sodalite cavities of fully K + -exchanged zeolite A. An additional KI molecule is retained in each large cavity as part of a near square planar K 4 I 3 + cation. A single crystal of Ag 1 2 -A, prepared by the dynamic ion-exchange of Na 1 2 -A (LTA) with aqueous 0.05 M AgNO 3 and washed with CH 3 OH, was placed in a stream of flowing 0.05 M KI in CH 3 OH at 294 K for 2 days. The crystal structure of the product, K 9 Si 1 2 Al 1 2 O 4 8 .(Ag 4 I 4 ) 0 . 5 .K 4 I 3 + , a = 12.290(1) A, was determined by single-crystal X-ray diffraction in the cubic space group Pm3m. It was refined with all measured reflections to the final error index R 1 = 0.077 (based on the 264 reflections for which F o > 4σ(F o )). The thirteen K + ions per unit cell are found at three crystallographically distinct positions: eight K + ions in the large cavity fill the 6-ring site, three K + ions fill the 8-rings, and two K + ions are opposite 4-rings in the large cavity. One iodide ion per unit cell lies opposite a 4-ring in the large cavity, held there by two 8-ring and the two 6-ring K + ions (K 4 I 3 + ). Two Ag + and two I - ions per unit cell are found on 3-fold axes in the sodalite cavity, indicating the formation of Age clusters (interpenetrating tetrahedra; symmetry T d ; diameter ca. 8.0 A) in half of the sodalite units. Each cluster (Ag-I = 2.97(2) A) is held in place by the coordination of its four Ag + ions to the zeolite framework (each Ag + cation is 2.48(1) A from three 6-ring oxygens) and by the coordination of its four I - ions to large-cavity K + ions through 6-rings (I-K = 2.72(6) A).