Intermetallic clathrates were discovered in the 1950s when the basic relations of alkali metals and group 14 elements were investigated [1, 2]. After the structural elucidation of Na8Si46 and NaxSi136 [3] the research field spread continuously, and representatives comprising Na, K, Rb and Cs were obtained. The only exception was the Li-containing clathrate and it was concluded that Li atoms are...

Clathrate-I-based materials are promising for waste-heat recovering applications via thermoelectric (TE) effects. However, the lack of highly efficient p-type hampers development clathrate-based TE devices. In this work, synthesis semiconductor Ba 7.8 Au 5.33 Ge 40.67 with clathrate-I structure is up-scaled by steel-quenching and spark plasma sintering treatment at 1073 K. A figure merit ZT ? 0...

We propose a novel method based on template matching for the recognition of liquid water, cubic ice (ice Ic), hexagonal Ih), clathrate hydrates, and different interfacial structures in atomistic coarse-grained simulations water ice. The two matrices represent staggered eclipsed conformations, which are building blocks crystals. algorithm is rotationally invariant highly robust against imperfect...

In the title compound, C(6)H(7)IN(+)·ClO(4) (-)·C(12)H(24)O(6), the proton-ated 4-iodo-anilinium cation inter-acts with the 18-crown-6 through three N-H⋯O hydrogen bonds, forming a rotator-stator-like structure. The cation, anion and 18-crown-6 mol-ecule all have crystallographically imposed mirror symmetry.

The formation of hydroquinone (HQ) clathrate and the guest behaviors binary (CH4 + CO2) gas mixtures were investigated by focusing on an application to separate CO2 from landfill gases. Spectroscopic measurements show that at two experimental pressures 20 40 bar, molecules are preferentially captured in HQ clathrates regardless composition. In addition, preferential occupation is observed more ...

For a further understanding of the phase transitions mechanism in type-I silicon clathrates K₈Si46, ab initio self-consistent electronic calculations combined with linear-response method have been performed to investigate the vibrational properties of alkali metal K atoms encapsulated type-I silicon-clathrate under pressure within the framework of density functional perturbation theory. Our lat...

Clathrate hydrates are of great importance in many aspects. However, hydrate formation and dissociation mechanisms, essential to all hydrate applications, are still not well understood due to the limitations of experimental techniques capable of providing dynamic and structural information on a molecular level. NMR has been shown to be a powerful tool to noninvasively measure molecular level dy...

The C1 N Q R spectrum of ortho-dichlorobenzene as a guest molecule in tetrakis(x-phQny\ethy\amine)-6i's(isothiocyanato)nickel(II), has been studied in the temperature range of 77 K to 250 K. At 77 K the clathrate has two resonances of equal intensity at 35.840 and 36.080 M H z , to be compared with those of pure orr/io-dichlorobenzene, where there are three lines at 35.580, 35.775 and 35.824 MH...

Semiconducting group 14 clathrates are inorganic host-guest materials with a close structural relationship to gas hydrates. Here we utilize this inherent structural relationship to derive a new class of porous semiconductor materials: noble gas filled group 14 clathrates (Ngx[M136], Ng = Ar, Kr, Xe and M = Si, Ge, Sn). We have carried out highlevel quantum chemical studies using periodic Local-...