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Monolithic pure silica gels with hierarchical macro-mesoporous structure have been synthesized via a spontaneous sol−gel process from silicon alkoxide using a structure-directing agent and a micelle-swelling agent. A monolithic body with well-defined co-continuous macropores is a result of concurrent phase separation and sol−gel transition induced by the polymerization reaction, whereas the mesopores are templated by the cooperative self-assembly of inorganic species, a structure-directing agent, and a micelle-swelling agent. These bimodal pore systems are formed spontaneously in a closed condition at a constant temperature. The following removal of surfactants by heat-treatment gives silica gels with hierarchical and fully accessible pores in discrete size ranges of micrometers and nanometers. The highly ordered 2D-hexagonal arrays of mesopores have been confirmed by X-ray diffraction measurements and FE-SEM observations. Furthermore, by further additions of the micelle-swelling agent, the mesostructural transition from well-ordered 2D-hexagonal arrays to mesostructured cellular foams (MCF) has been induced accompanied by minor modifications of the micrometer-range structure.

Potassium clusters are incorporated into supercages of zeolite LTA crystals, with the supercages arrayed in a simple cubic structure at a number density of 5.3 x 10 20 cm " 3 . About four 4y electrons of K atoms are included in each cluster. The ac magnetic susceptibility increases dramatically with decreases in temperature below 8 K, and shows ferromagnetism below about 4 K. The effective magnetic moment per supercage is estimated to be about 0.13/x* at 1.7 K. Magnetic properties resemble those of a reentrant spin glass. PACS numbers: 75.50.Lk, 33.20.-t, 36.20.-r, 78.65.EzAn isolated metal cluster of a nonmagnetic element is expected to exhibit a magnetic moment when it has an odd number of electrons [1], The temperature dependence of the magnetic susceptibility of these clusters is expected to be of the Curie type [2]. If such clusters are arranged periodically and their magnetic moments mutually interact, the resulting materials are expected to be significantly different, with respect to magnetic properties, not only from the isolated clusters but also from the original bulk material. Very recently, ferromagnetism has been reported in organic molecular crystals with no magnetic element, such as p-NPNN [3] and C 6u TDAE [4]. In these materials, ferromagnetism may be realized by the mutual interaction between molecular magnetic moments or by itinerant electrons.The framework of zeolites is crystalline, and includes well defined cages specific to the type of zeolite. Cations, for example, Na + , are distributed in the space of the framework. The chemical formula is given as M n A\ n -Si m 02(/!+m), where M denotes the kind of cation. Alkali metal clusters of various sizes are generated in zeolites by introducing guest alkali metal atoms. Extensive optical and magnetic measurements have been performed on these materials [5-10].In LTA, which is a type of zeolite, supercages with an inner diameter of 11 A are arrayed in a simple cubic structure with a number density of 5.3x 10 20 cm -3 , and are connected by shared windows with an inner diameter of 5 A. In the present paper, K clusters are generated in the supercages of K-exchanged LTA, and the electronic interaction between K clusters is realized through the windows between the supercages. Such arrayed clusters are called a cluster crystal [11]. It is confirmed by the optical reflection spectrum that each K cluster includes about four As electrons of guest K atoms. It is revealed from the measurement of the ac magnetic susceptibility that the K cluster crystal shows ferromagnetism below about 4 K.Original Na-form LTA powder was transformed by ion exchange into K form in the KC1 aqueous solution, and washed with distilled water. The Si-to-Al ratio of LTA

Monolithic ethane−silica gels with well-defined co-continuous macropores and highly ordered mesopores have been synthesized via a spontaneous route from silicon alkoxide with the aid of a structure-directing agent. While the macropores are formed by the concurrent phase separation and sol−gel transition induced by the polymerization reaction, the mesopores are templated by the self-organization of the structure-directing agent. Starting from a homogeneous mixture of the starting components, all the structure formation processes take place spontaneously in closed conditions at a constant temperature. Subsequent evaporation drying and heat treatment result in gels with hierarchical and fully accessible pores in discrete size ranges of micrometer and nanometer. While the local alignment of the mesopores is confirmed by FE-SEM observation, the long-range mesoscale order over the whole sample is evidenced by X-ray diffraction measurements. With the addition of a micelle-swelling agent, the mesostructural transition from 2D-hexagonal order to mesostructured cellular foam, MCF, has been observed without disturbing the macroporous framework structure.