Trapezoidal geometry

Fig. 18.5 Scanning electron microscope images showing cross sections of ARROWS with (a) trapezoidal geometry formed from an aluminum core, (b) rectangular geometry formed from an SU8 core, and (c) arched geometry formed from a reflowed photoresist core...

The calculation of the secondary current distribution in a cell of trapezoidal geometry illustrates the effect of the polarization resistance on the uniformity of the current and potential distribution at an electrode. Indeed, because the electrode potential is a unique function of the current density, E =f(i), the distributions of the current and of the potential are linked. 

Gerhartz, W., Poshusta, R.D., Michl, J. (1976), Excited Potential Energy Hypersurfaces for at Trapezoidal Geometries. Relation to Photochemical 2s + 2s Processes, J. Am. Chem. Soc. 98, 6427. 

Figure 26. The ORTEP plot of [Se S2CN(CH2)5 2], showing the planar trapezoidal geometry at the metal center in the [Se(S2CNR2)2] complexes.

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