“…Si [21,[50][51][52][53][54][55], a-Si [56][57][58], SiC [59,60], Ge [19,21,51,61,62] a-Ge [63] Si:Ge [31,[64][65][66], graphite [67], diamond [68][69][70][71]. Less functional p-block elements, but with equally intriguing chemical physics, illustrated in figure 16 for sulphur: α-Sn [48,72], B [48,73], P [48,74], As [48,74], S [48,49], Se [48,75], Te [48,76].…”