b"\n_START_ARTICLE_\nCalcogenur\n_START_SECTION_\nMonocalcogenurs\n_START_PARAGRAPH_\nEls monocalcogenurs met\xc3\xa0l\xc2\xb7lics tenen la f\xc3\xb3rmula ME, on M = un metall de transici\xc3\xb3 i E = S, Se, Te. _NEWLINE_Importants monocalcogenurs inclouen alguns pigments, especialment el sulfur de cadmi. Molts minerals s\xc3\xb3n monosulfurs.\n_START_SECTION_\nDicalcogenurs\n_START_PARAGRAPH_\nEls dicalcogenurs met\xc3\xa0l\xc2\xb7lics tenen la f\xc3\xb3rmula ME\xe2\x82\x82, on M = un metall de transici\xc3\xb3 i E = S, Se, Te..\n_START_SECTION_\nLa pirita i els disulfurs relacionats\n_START_PARAGRAPH_\nLa pirita de ferro normalment es descriu com Fe\xe2\x82\x82\xe2\x82\x8a i l'ani\xc3\xb3 persulfur com S\xe2\x82\x82\xc2\xb2\xe2\x81\xbb.\n_START_SECTION_\nTricalcogenurs\n_START_PARAGRAPH_\nDiversos metalls, principalment del grups Ti, V, Cr i Mn, tamb\xc3\xa9 formen tricalcogenurs. Aquests materials normalment es descriuen com M\xe2\x81\xb4\xe2\x81\xba(E\xe2\x82\x82\xc2\xb2\xe2\x81\xbb)(E\xc2\xb2\xe2\x81\xbb) (on E = S, Se, Te). n exemple ben conegut \xc3\xa9s el triselenur de niobi."