Water, twisting mode

The downward shift of the Mo=0 vibration, observed in the Raman and infrared spectra of the catalyst, was concomitant with the development of the water twisting mode observed in the INS spectrum. The alternative possibility, that adsorption of water on calcined molybdate/ alumina was dissociative, was not consistent with the spectra. Dissociative chemisorption implies the formation of a Mo-OH group. Such groups have been identified by INS of hydrogen molybdenum... 

As shown in Fig. 6(a), for an isolated water molecule there are three types of librational modes, twist(T), wag(W) and rock(R). Using the factor group analysis for the four molecules in a primitive cell, 12 librational modes in XI phase are divided into... 

A TciT simple mode of filtering aqueous fiuids, which are not injured by exposure to the air, is to draw them off from one vessel to another, by means of a number of threads of loosely twisted cotton or worsted arranged in the form of a syphon. The little cotton rope at once performs the operations of de cantation and filtration. This method is often convenient for sucking off the water from small quantities of precipitates. 

Vibrational modes of water. Shown are the internal modes (a) symmetric stretch, (b) bending, (c) asymmetric stretch, and the librational modes (d) wag, (e) twist, and (f) rock. Not shown are the three hindered translational modes. 

In a similar manner, the vibrational modes of coordinated water molecules, such as wagging, twisting and rocking (which cannot occur in lattice water molecules) become infrared active, the resulting bands occurring in the region 880-650 cm (11.36-15.38 pm). (For large water clusters see reference 36.)... 

Super-twisted GH mode Waters and Raynes UK Patent, Proceedings of 3rd... 

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