[erlosrequiem]

Q: In the case of [N(CH₃)₄]₂[CoBr₄], give the oxidation state, dⁿ configuration, coordination number and geometry of the metal centre.
Calculate the CFSE in units of Δ
Calculate the magnetic moment, μ
Give the IUPAC name of the complex.

Could anyone let me know if I'm right here:
A:
oxidation state = 2+
dⁿ config= d⁷
coordination number = 4
geometry = tetrahedral
CFSE = originally I had calculated this to be -4/5Δ_o but I'm now thinking it might be 4/5Δ_T. Can someone clarify which it would be?
Magnetic moment = sqrt(15) μ_B
IUPAC name: tetrabromocobaltate tetramethylammonium

[mjc123]

oxidation state = 2+

Yes

dn config= d7

Yes

coordination number = 4

Yes

geometry = tetrahedral

Yes

CFSE = originally I had calculated this to be -4/5Δo but I'm now thinking it might be 4/5ΔT. Can someone clarify which it would be?
Well, it's tetrahedral, so....  And I don't think it's -4/5. What is the order of the orbitals in tetrahedral geometry?
Magnetic moment = sqrt(15) μB

I think so, but magnetochemistry was never my strongest suit

IUPAC name: tetrabromocobaltate tetramethylammonium

Name cation first, and indicate oxidation state of Co

Mod Edit: by adding quotes for clarity

[mjc123]

To be a bit more clear

CFSE = originally I had calculated this to be -4/5Δo but I'm now thinking it might be 4/5ΔT. Can someone clarify which it would be?

Well, it's tetrahedral, so....  And I don't think it's -4/5. What is the order of the orbitals in tetrahedral geometry?

Magnetic moment = sqrt(15) μB

I think so, but magnetochemistry was never my strongest suit

That was two questions and answers