4-coordinate: tetrahedral (p-block element, 2 lone pairs)

[Se(P{CH(SiMe₃)₂}₂]

Formula Unicode styled: 
[Se(P{CH(SiMe₃)₂}₂]
Compound name(s): 
bis{bis(trimethylsilyl)methyl)phosphanyl}-selenium
Central atom: 
Attached groups: 
Charge on central atom: 
0
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V2C2O-IIE8B2Z0L0X2»
[MLXZ]𝘲 class: 
[MX2]
MLXZ class (ENC, equivalent neutral class): 
MX2

[Se₂(Me)₂(μ₂-C₂H₄)(NbCl₅)₂]

Formula Unicode styled: 
[Se₂(Me)₂(μ₂-C₂H₄)(NbCl₅)₂]
Compound name(s): 
(μ₂-dimethylene)-bis[methyl-(pentachloro-niobium)-selenium]
Central atom: 
Charge on central atom: 
0
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V4C3OIIE8B3L0X2Z1»
[MLXZ]𝘲 class: 
[MX2Z1]
MLXZ class (ENC, equivalent neutral class): 
MX2Z1

[Se(COMe)(C₆H₄NMe₂)]

Formula Unicode styled: 
[Se(COMe)(C₆H₄NMe₂)]
Compound name(s): 
dimethylaminophenyl-acyl-selenium
Central atom: 
Charge on central atom: 
0
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V2C2OIIE8B2Z0L0X2»
[MLXZ]𝘲 class: 
[MX2]
MLXZ class (ENC, equivalent neutral class): 
MX2

[Se(COMe)(Mes)]

Formula Unicode styled: 
[Se(COMe)(Mes)]
Compound name(s): 
mesityl-acyl-selenium
Central atom: 
Attached groups: 
Charge on central atom: 
0
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V2C2OIIE8B2Z0L0X2»
[MLXZ]𝘲 class: 
[MX2]
MLXZ class (ENC, equivalent neutral class): 
MX2

[Se{C₆H₃(CF₃)₂}₂]

Formula Unicode styled: 
[Se{C₆H₃(CF₃)₂}₂]
Compound name(s): 
bis{3,5-bis(trifluoromethyl)phenyl}-selenium
Central atom: 
Charge on central atom: 
0
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V2C2OIIE8B2Z0L0X2»
[MLXZ]𝘲 class: 
[MX2]
MLXZ class (ENC, equivalent neutral class): 
MX2

[Se(TeTol)₂]

Formula Unicode styled: 
[Se(TeTol)₂]
Compound name(s): 
{bis(tolyl)tellanyl)-selenium
Central atom: 
Attached groups: 
Charge on central atom: 
0
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V2C2O-IIE8B2Z0L0X2»
[MLXZ]𝘲 class: 
[MX2]
MLXZ class (ENC, equivalent neutral class): 
MX2

[W{Se(Ph)}(μ₂-Se)(η₅-C₅Me₅)]₂

Formula Unicode styled: 
[W{Se(Ph)}(μ₂-Se)(η₅-C₅Me₅)]₂
Compound name(s): 
bis-[(phenyl)-(μ₂-selenido)-{(pentamethylcyclopentadienyl)-tungsten}]
Central atom: 
Attached groups: 
Charge on central atom: 
0
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V2C2O-IIE8B2Z0L0X2»
[MLXZ]𝘲 class: 
[MX2]
MLXZ class (ENC, equivalent neutral class): 
MX2

[Se(Ph){(W(μ₂-Se)(η₅-C₅Me₅)]₂

Formula Unicode styled: 
[Se(Ph){(W(μ₂-Se)(η₅-C₅Me₅)]₂
Compound name(s): 
bis-[(phenyl)-(μ₂-selenido)-{(pentamethylcyclopentadienyl)-tungsten}]
Central atom: 
Attached groups: 
Charge on central atom: 
0
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V2C2OOE8B2Z0L0X2»
[MLXZ]𝘲 class: 
[MX2]
MLXZ class (ENC, equivalent neutral class): 
MX2

[(μ₂-Se)Re₂(CO)₄(Cp)₂]

Formula Unicode styled: 
[(μ₂-Se)Re₂(CO)₄(Cp)₂]
Compound name(s): 
(μ₂-selenido)-bis(η⁵-cyclopentadienyl)-tetracarbonyl-di-rhenium
Central atom: 
Attached groups: 
Charge on central atom: 
0
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V2C2O-IIE8B2Z0L0X2»
[MLXZ]𝘲 class: 
[MX2]
MLXZ class (ENC, equivalent neutral class): 
MX2

[Se(TePh)(TeI₂Ph)]

Formula Unicode styled: 
[Se(TePh)(TeI₂Ph)]
Compound name(s): 
(diiodo-phenyl-tellurium)-(phenyl-tellurium)-selenium
Central atom: 
Attached groups: 
Charge on central atom: 
0
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V2C2O-IIE8B2Z0L0X2»
[MLXZ]𝘲 class: 
[MX2]
MLXZ class (ENC, equivalent neutral class): 
MX2

[Se(C₆H₄-C₆H₄)]

Formula Unicode styled: 
[Se(C₆H₄-C₆H₄)]
Compound name(s): 
(biphenyl-κC²)-selenium
Central atom: 
Charge on central atom: 
0
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V2C2OIIE8B2Z0L0X2»
[MLXZ]𝘲 class: 
[MX2]
MLXZ class (ENC, equivalent neutral class): 
MX2

[Se₂(CN)₂{(CH₂)₂C₆H₄}]

Formula Unicode styled: 
[Se₂(CN)₂{(CH₂)₂C₆H₄}]
Compound name(s): 
1,3-phenylene-bis(selenocyanate)
Central atom: 
Charge on central atom: 
0
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V2C2OIIE8B2Z0L0X2»
[MLXZ]𝘲 class: 
[MX2]
MLXZ class (ENC, equivalent neutral class): 
MX2

catena–3D-[Se₃Al₂]

Formula Unicode styled: 
catena–3D-[Se₃Al₂]
Compound name(s): 
di-aluminum-tri-selenium
aluminium selenide
Central atom: 
Attached groups: 
Charge on central atom: 
1
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V4C3O-IIE8B3Z0L0X3»
[MLXZ]𝘲 class: 
[MX3]+
MLXZ class (ENC, equivalent neutral class): 
MX2Z1

[Se(NSO)₂]

Formula Unicode styled: 
[Se(NSO)₂]
Compound name(s): 
di(sulfinylamino)-selenium
Central atom: 
Attached groups: 
Charge on central atom: 
0
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V2C2OIIE8B2Z0L0X2»
[MLXZ]𝘲 class: 
[MX2]
MLXZ class (ENC, equivalent neutral class): 
MX2

catena–2D-[Se₂Ge]

Formula Unicode styled: 
catena–2D-[Se₂Ge]
Compound name(s): 
catena-[di(μ₂-seleno)-germanium]
germanium selenide - α
Central atom: 
Attached groups: 
Charge on central atom: 
0
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V2C2O-IIE8B2Z0L0X2»
[MLXZ]𝘲 class: 
[MX2]
MLXZ class (ENC, equivalent neutral class): 
MX2

catena–2D-[Se₃(μ₃-As)₂]

Formula Unicode styled: 
catena–2D-[Se₃(μ₃-As)₂]
Compound name(s): 
[di(μ₃-arsenic)-triselenium)]
Laphamite
Central atom: 
Attached groups: 
Charge on central atom: 
0
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V2C2O-IIE8B2Z0L0X2»
[MLXZ]𝘲 class: 
[MX2]
MLXZ class (ENC, equivalent neutral class): 
MX2

catena-[Se₂(Tl)]⊖

Formula Unicode styled: 
catena-[Se₂(Tl)]⊖
Compound name(s): 
catena-[di(μ₂-seleno)-thallium(1-)]
Central atom: 
Charge on central atom: 
-1
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V2C2O-IIE8B2L0X1Z1»
[MLXZ]𝘲 class: 
[MX1Z1]-
MLXZ class (ENC, equivalent neutral class): 
MX2

[Se(PBuᵗ₂)₂]

Formula Unicode styled: 
[Se(PBuᵗ₂)₂]
Compound name(s): 
bis-(di-t-butylphosphorus)selenium
Central atom: 
Charge on central atom: 
0
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V2C2O-IIE8B2Z0L0X2»
[MLXZ]𝘲 class: 
[MX2]
MLXZ class (ENC, equivalent neutral class): 
MX2

[Se{P(Se)Ph₂}₂]

Formula Unicode styled: 
[Se{P(Se)Ph₂}₂]
Compound name(s): 
bis-{diphenyl(seleno)phosphanyl)}-selenium
Central atom: 
Attached groups: 
Charge on central atom: 
0
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V2C2O-IIE8B2Z0L0X2»
[MLXZ]𝘲 class: 
[MX2]
MLXZ class (ENC, equivalent neutral class): 
MX2

[Se{Gd(η₅-C₅Me₅)₂}]₂

Formula Unicode styled: 
[Se{Gd(η₅-C₅Me₅)₂}]₂
Compound name(s): 
bis-[{bis(pentamethylcyclopentadienyl)-gadolinium}-selanium]
Central atom: 
Attached groups: 
Charge on central atom: 
0
Compound type: 
Valence Number (VN) = 𝘹 + 2𝘻 : 
Oxidation Number (ON) (Roman numerals): 
Coordination Number (CN, sum of attached group denticities): 
Electron Number (EN) = 𝘮 + 𝘹 +2𝘭: 
Summary of calculated classifications: 
Se«V2C2O-IE8B2Z0L0X2»
[MLXZ]𝘲 class: 
[MX2]
MLXZ class (ENC, equivalent neutral class): 
MX2