Hofmann-dahxn-type

One of the problems to be solved for the formation trend of Hofmann-(long-carbon-chain a,oo-diaminoalkane)-type series of inclusion compounds is to interpret the reason why Hofmann-dahxn-type host cannot accommodate xylidines as guest, which Hofmann-dabn-type host can do even with the shorter carbon chain in the full length than dahxn. In order to solve the problem we need more information about the crystal structures of the series. The structure analyses of Hofmann-dahxn-type m-and p-toluidine inclusion compounds are in progress. 

Hofmann-dahxn-type (dahxn = 1,6-diaminohexane) [8,9] their three-... 

During the research work on these clathrate compounds we discovered a rare case of conversion from an apparently more stable coordination complex to a less stable clathrate compound for the Hofmann-dahxn-type series. The -toluidine compound obtained under the experimental conditions similar to those for the - and the m -toluidine clathrates was not a clathrate but a coordination complex [Cd( -CH3C6Hi NH2) 2 (dahxn)][Ni(CN)if], which turned to a clathrate Cd(dahxn)Ni(CN)... 

A phase transition probably to a superlattice structure has been observed for Hofmann-dahxn-type -toluidine clathrate at 200 K. Above this temperature the atomic temperature factors of the guest molecule increase steeply to suggest that the librational motion of the guest molecule is excited thermally. The details of the phase transition is still unknown, although it should be related to motion of the guest molecule. 

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