Promethocene is a metal-organic compound of promethium with the chemical formula Pm(C5H5)3.

Promethocene is different from cyclopentadiene complexes of general transition metals and is considered to be ionically bonded.

[1] Theoretical calculations show that its Pm natural population analysis (NPA) electronic configuration is 6s0.115d1.194f2.21.

[2] Promethocene can be obtained by reacting anhydrous promethium(III) chloride and sodium cyclopentadienide in a tetrahydrofuran medium:[1] Promethocene decomposes when exposed to water to produce promethium(III) hydroxide and cyclopentadiene.

MgCpBr (TiCp2Cl)2 TiCpCl3 TiCp2S5 TiCp2(CO)2 TiCp2Me2 VCpCh VCp2Cl2 VCp(CO)4 (CrCp(CO)3)2 Fe(η5-C5H4Li)2 ((C5H5)Fe(C5H4))2 (C5H4-C5H4)2Fe2 FeCp2PF6 FeCp(CO)2I CoCp(CO)2 NiCpNO ZrCp2ClH MoCp2Cl2 (MoCp(CO)3)2 RuCp(PPh3)2Cl RuCp(MeCN)3PF6