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complex cations were self-assembled to form +12-charged supramolecular octahedrons that are closely packed in a face-centered cubic (fcc) structure. In this structure, ten monovalent anions are accommodated in each hydrophilic tetrahedral interstice to create an adamantane-shaped anionic cluster, while two anions are each encapsulated in each octahedral interstice and in the center of each supramolecular octahedron. The use of divalent anions (SO 4 2¹ and SiF 6 2¹ ) also produced an analogous fcc structure made up of the +12-charged supramolecular octahedrons. In this case, six divalent anions are accommodated in each hydrophilic tetrahedral interstice to form an octahedron-shaped anionic cluster, completing a giant zinc blende lattice structure where all cations and anions are separately aggregated into the +12-charged octahedrons and the ¹12-charged octahedrons, respectively. The site selective aggregation of two kinds of inorganic anions ( Ionic crystals that consist of cationic and anionic species, represented by metal oxides and metal halides, are ubiquitous in nature, and some of them have been widely utilized as functional materials, such as ferroelectric devices, nonlinear optical materials, and superconductors. 13 It is one of the most fundamental laws of nature that cationic and anionic species are alternately arranged in crystal to avoid Coulombic repulsion, as well as to gain Coulombic attraction (Figure 1a). The most typical examples are simple inorganic salts having sodium chloride (NaCl) and zinc blende (ZnS) structures; each monovalent ion is octahedrally surrounded by six monovalent counter ions in sodium chloride structure, while each divalent ion is tetrahedrally surrounded by four divalent counter ions in zinc blende structure. 4 If Coulombic repulsion is eased by the presence of polar molecules, such as water molecules of crystallization, a few homologous ionic species may possibly approach each other. 5 In addition, homologous ionic species are possibly self-assembled to form ionic linkages or aggregates if they possess both electron-donating and electronaccepting sites, as found in inorganic salts of hydrogen sulfate and dihydrogen phosphate.6 This is also the case for some coordination compound having both unsaturated metal centers and free coordination groups in one molecule. 8 Thus, the aggregation of homologous cationic or anionic species in crystals has often been observed in inorganic and coordination systems. Nevertheless, ionic crystals that consist of both cationic aggregates and anionic aggregates appear to be unknown (Figure 1b), and the creation of this class of compounds, which contradicts the alternate arrangement of cationic and anionic species of natural ionic crystals, remains a great challenge.As part of our ongoing efforts in the development of multinuclear and supramolecular coordination systems based on chiral metalloligands with thiol-containing amino acids,

The 1:1 reaction of [Au2(dppe)(d-Hpen)2] (dppe: 1,2-bis(diphenylphosphino)ethane, d-H2pen: d-penicillamine) with Ni(CH3COO)2·4H2O in ethanol, followed by the vapor diffusion of diethyl ether, gave blue-green crystals of [Au4Ni2(dppe)2(d-pen)4]. This compound showed single-crystal-to-single-crystal conversion on soaking in water, accompanied by the drastic change in complex-molecular arrangements from straight chain to helix structures.

A unique gold(I)copper(II) 1D polymeric system, [Cu{Au 2 (L Cn )(pen) 2 }] (L Cn = Ph 2 P(CH 2 ) n PPh 2 (n = 3, 4, and 5); H 2 pen: penicillamine), which involves three types of helices (single-stranded homochiral helix, single-stranded meso helix, and triple-stranded homochiral helix), is reported. This system was created from linear digold(I) metalloligands, which possess a bis (diphenylphosphino) The design and creation of helix structures have long been a subject of considerable attention in a wide range of research fields, not only because of their relevance to biologically important structures such as DNA and α-helices of proteins, 1 but also because of being an effective way of introducing chirality into molecules.2 Self-assembly of metal ions and bridging ligands through coordination bonds is the most common approach to produce infinite, uniform helices.3 To date, several 1D helix coordination polymers have been synthesized using this approach, and their unique functionalities such as luminescence, 4 magnetic, 5 and catalytic properties, 6 as well as their chemical sensing 7 and chiral recognition abilities, 8 have been reported. Most of these helix coordination polymers possess single-stranded structures with either left-handedness or right-handedness. On the other hand, other types of coordination polymers with more unique structures®such as multiplestranded helices, which contain two or more intertwined helical chains; 9 tubular helices, which have a large 1D channel inside the helix; 4c,9a,9e,10 and meso helices, which consist of alternate right-and left-handed helical loops 11,12 ®are highly limited in number. In addition, the controlled construction of different types of helix structures in a rational manner has rarely been achieved, although helix handedness has often been controlled by asymmetric center(s) contained in bridging ligands. 3,13Therefore, the finding of general factors that govern helix topologies is of great demand in this research field.As part of our continuing studies on the stepwise construction of metallosupramolecular architectures by using multifunctional metalloligands with chiral sulfur-containing amino acids such as cysteine (H 2 cys) and penicillamine (H 2 pen), 10a,1417 we recently designed and synthesized linear digold(I) metallo-¹ coordination arms that are linked by bis(diphenylphosphino)alkane (L Cn = Ph 2 P(CH 2 ) n PPh 2 ; n = 1 and 2) through AuP bonds. (Figure 1a) and closed-bridging (Figure 1b) coordination modes, respectively, to form discrete metallocyclic structures. 16,17 We expected that the employment of analogous metalloligands having a longer alkyl chain; n > 2) will lead to the creation of infinite polymeric structures by adopting the extended bridging mode (Figure 1c

The 1:1 mixing of a pair of enantiomers of a cyclic Au(I)4Co(III)2 hexanuclear complex having penicillaminate (pen) and 1,2-bis(diphenylphosphino)ethane (dppe), [Au4Co2(dppe)2(d-pen)4](2+) (d4-[1](2+)) and [Au4Co2(dppe)2(l-pen)4](2+) (l4-[1](2+)), in solution produced an additional stereoisomer, [Au4Co2(dppe)2(d-pen)2(l-pen)2](2+) (d2l2-[1](2+)), because of the scrambling of [Co(d-pen)2](-) and [Co(l-pen)2](-) units between d4-[1](2+) and l4-[1](2+). Upon crystallization with NO3(-), the three stereoisomers were independently crystallized to form three different kinds of crystals, homochiral crystals of d4-[1](NO3)2, homochiral crystals of l4-[1](NO3)2, and heterochiral crystals of d2l2-[1](NO3)2, showing a unique example of the self-recognition and organization of three stereoisomers upon crystallization.