10-coordinate: ⑤-●-⑤ metallocene

[Eu(η⁹-C₉H₉)₂]

Formula Unicode styled: 
[Eu(η⁹-C₉H₉)₂]
Compound name(s): 
bis(cyclononatetraenyl)-europium
Central atom: 
Europium
Attached groups: 
C₉H₉ (η⁹-cyclononatetraenyl)
Charge on central atom: 
0
Compound type: 
Molecular
Valence Number (VN) = 𝘹 + 2𝘻 : 
VN: 2
Oxidation Number (ON) (Roman numerals): 
ON: (II)
Coordination Number (CN, sum of attached group denticities): 
CN: 10
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
EN: 27
Summary of calculated classifications: 
Eu«V2C10OIIE27B10Z0X2L8»
[MLXZ]𝘲 class: 
[MX2L8]
MLXZ class (ENC, equivalent neutral class): 
MX2L8

[Sm(η⁹-C₉H₉)₂]

Formula Unicode styled: 
[Sm(η⁹-C₉H₉)₂]
Compound name(s): 
bis(cyclononatetraenyl)-samarium
Central atom: 
Samarium
Attached groups: 
C₉H₉ (η⁹-cyclononatetraenyl)
Charge on central atom: 
0
Compound type: 
Molecular
Valence Number (VN) = 𝘹 + 2𝘻 : 
VN: 2
Oxidation Number (ON) (Roman numerals): 
ON: (II)
Coordination Number (CN, sum of attached group denticities): 
CN: 10
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
EN: 26
Summary of calculated classifications: 
Sm«V2C10OIIE26B10Z0X2L8»
[MLXZ]𝘲 class: 
[MX2L8]
MLXZ class (ENC, equivalent neutral class): 
MX2L8

[Tm(η⁹-C₉H₉)₂]

Formula Unicode styled: 
[Tm(η⁹-C₉H₉)₂]
Compound name(s): 
bis(cyclononatetraenyl)-thulium
Central atom: 
Thulium
Attached groups: 
C₉H₉ (η⁹-cyclononatetraenyl)
Charge on central atom: 
0
Compound type: 
Molecular
Valence Number (VN) = 𝘹 + 2𝘻 : 
VN: 2
Oxidation Number (ON) (Roman numerals): 
ON: (II)
Coordination Number (CN, sum of attached group denticities): 
CN: 10
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
EN: 29
Summary of calculated classifications: 
Tm«V2C10OIIE29B8Z0X2L6»
[MLXZ]𝘲 class: 
[MX2L6]
MLXZ class (ENC, equivalent neutral class): 
MX2L6