Trimetasphere carbon nanomaterials (TMS), also known as trimetallic nitride endohedral metallofullerenes, are a family of endohedral metallofullerenes (EMF). The first TMS adduct

Adduct

An adduct is a product of a direct addition of two or more distinct molecules, resulting in a single reaction product containing all atoms of all components. The resultant is considered a distinct molecular species...

, a Diels-Alder cycloadduct of Sc₃N by C₈₀, was reported by Dorn et al. in 2002. It was not until 2005 that other derivatives were reported. The most abundant TMS consist of 80 carbon

Carbon

Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...

 atoms encompassing and forming a complex with three metal atoms and a nitrogen

Nitrogen

Nitrogen is a chemical element that has the symbol N, atomic number of 7 and atomic mass 14.00674 u. Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.08% by volume of Earth's atmosphere...

 atom (trimetallic nitride clusters, M₃N).

Examples

Examples of metals forming trimetallic nitride clusters include :

• Scandium
  Scandium
  Scandium is a chemical element with symbol Sc and atomic number 21. A silvery-white metallic transition metal, it has historically been sometimes classified as a rare earth element, together with yttrium and the lanthanoids...
  
  , Sc₃N
• Yttrium
  Yttrium
  Yttrium is a chemical element with symbol Y and atomic number 39. It is a silvery-metallic transition metal chemically similar to the lanthanides and it has often been classified as a "rare earth element". Yttrium is almost always found combined with the lanthanides in rare earth minerals and is...
  
  , Y₃N
• Erbium
  Erbium
  Erbium is a chemical element in the lanthanide series, with the symbol Er and atomic number 68. A silvery-white solid metal when artificially isolated, natural erbium is always found in chemical combination with other elements on Earth...
  
  , Er₃N
• Lutetium, Lu₃N
• Gadolinium
  Gadolinium
  Gadolinium is a chemical element with the symbol Gd and atomic number 64. It is a silvery-white, malleable and ductile rare-earth metal. It is found in nature only in combined form. Gadolinium was first detected spectroscopically in 1880 by de Marignac who separated its oxide and is credited with...
  
  , Gd₃N