过渡元素(transition elements)是元素周期表中从ⅢB族到VⅢ族的化学元素 。这些元素在原子结构上的共同特点是价电子依次充填在次外层的d 轨道上 ，因此，有时人们也把镧系元素和锕系元素包括在过渡元素之中 。另外，ⅠB族元素(铜、银、金)在形成+2和 +3 价化合物时也使用了d电子；ⅡB族元素(锌、镉、汞)在形成稳定配位化合物的能力上与传统的过渡元素相似，因此，也常把ⅠB和ⅡB族元素列入过渡元素之中。
Cupric bromide
Copper(II) oxide
Copper(I) chloride
Tetrakis(acetonitrile)copper(I) hexafluorophosphate
Titanocenedichloride
Ferrocenemethanol
Tetrakis(triphenylphosphine)platinum(0)
Chloro{(S)-(-)-2,2'-bis[di(3,5-xylyl)phosphino]-1,1'-binaphthyl}[(2S)-(+)-1-(4-methoxyphenyl)-1-(4-methoxyphenyl-kC)-3-methyl-1,2-butanediamine]ruthenium(II)
Cyclopentadienyl iron(II) dicarbonyl dimer
Cyclopentadienyltitanium trichloride
Bis(tricyclohexylphosphine)nickel(II) chloride
1,1'-Dibromoferrocene
Dicarbonylcyclopentadienylcobalt
(Bicyclo[2.2.1]hepta-2,5-diene)dichloropalladium(ii)
Dichloro(1,10-phenanthroline)copper
Dichloro(1,5-cyclooctadiene)platinum(II)
Dichloro(cycloocta-1,5-diene)ruthenium(II)
Dichloro(p-cymene)ruthenium(II) Dimer
Dichloro(pentamethylcyclopentadienyl)iridium(III) dimer
Dichlorobis(tricyclohexylphosphine)palladium(II)
Dichlorotris(triphenylphosphino)ruthenium (II)
trans-Bis(dicyclohexylphenylphosphino)nickel(II) chloride
Dichloro[9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene]palladium(II)
1-Hydroxytetraphenyl-cyclopentadienyl(tetraphenyl-2,4-cyclopentadien-1-one)-u-hydrotetracarbonyldiruthenium(II)
(1,5-Cyclooctadiene)bis(methyldiphenylphosphine)iridium(I) hexafluorophosphate
Tris(2,2-bipyridyl)ruthenium(II) chloride hexahydrate
fac-Tris(2-phenylpyridine)iridium
Dihydrogen Di-μ-chlorotetrakis(di-tert-butylphosphinito)dipalladate
