Bands seven symmetry classes

There are altogether seven symmetry classes of one-sided bands. They are illustrated in Figure 8-5 for a suitable motif, a black triangle. A brief characterization of the seven classes is given here, following their notation ... 

Figure 8-5. The seven symmetry classes of one-sided bands.

The seven one-dimensional symmetry classes for the one-sided bands are illustrated by patterns of Hungarian needlework in Figure 8-6 [6], This kind of needlework is a real one-sided band. Figure 8-7 presents a scheme to facilitate establishing the symmetry class of one-sided bands [7],... 

The local symmetry of the ring is reduced to in centrally bonded complexes with a resultant increase in the number of IR bands from four to seven (Table 4-9). In addition, a metal-ring stretching frequency is present in the far IR in complexes exhibiting this bonding mode. Some typical complexes in this class are listed in Table 4-10. 

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