for metallocenes how many d orbitals are there
there are 5 d orbitals
what are the 5 d orbitals for metallocenes and arenes
u have the delta (2) the sigma (1) and the pi* (2)
e2 is what
the delta orbitals
what d orbitals are the delta ones
the dx2-y2 and the dxy
what orbital is the a1
the sigma
also the dz^2
what orbital is the e1
the pi*
the dzx and dzy
how many nodes do each of the 5d orbitals for metallocenes and arenes have
the sigma has no nodes,, a1, dz^2 ,, makes sense bc look at the shape of dz^2
the pi* has 1 nodal plane,, dzx, dzy ,, standing up
the sigma has 2 nodal planes,, dx2-y2 and dxy ,, sandwhich
when we have the delta, sigma and pi*,, what energy order are they
u have the
pi* e1
sigma a1
delta e2
what differs with the 5d orbitals when were working with the front TM vs when were workign with Fe onwards
at the beginning the delta and the sigmas are basically degenerate meaning when we fill them up we do them as if theyre degen,, we can fill them at the same time
after Fe,, the delta orbital is destabilised due to the contraction when Z (nuc charge) increases ,, the obritals get pulled in closer weakening the delta bonding,, meaning we flip the sigma (a1) and the delta (e2) ,, so now the sigma is lower energy than the delta.
metallocenes always have the metal in what charge
they always have it in the +2 oxidation state!!!
arenes always have the metal in what oxidation state
arenes have the metal in the M(0) oxidation state, aka their normal form
metalocenes will have what ligand type
cp
arenes will have what ligand type
bz
diff between front and back TM
u either have the delta as the lowest energy ( front)
or u have the sigma as the lowest due to Zeff increasing after Fe.
difference between the metallocenes and the arenes
metallocenes will have the delta and the sigma at degen energies
arenes wil have the delta energy lower than sigma,, so u have to fill in the delta and then the sigma,, not at the same time.
why is delta bonding in arenes more signidicant,, making the gap between the delta and the sigma larger
bc the metal is in a 0 ixidation state,, making the orbitals larger,, so theres more e- ,, so delta bonding is more significant,, making the gap between delta and sigma larger
the delta,, aka e2 has how many lines,, aka how many e- can fit here
4 e- can fit here as theres 2 lines,, hence the e2!!
how many lines does a1 have
1
how many lines does e1 have
1
M(cp)2 means what
means its a metallocene meaning its M2+,, also means that u dill the e2 and the a1 as degen
M(cp)2 has long.u as 1.95BM
when oxidised to M(cp)2 + ,, its diamagnetic
when the same metal forms a bisarene, M(bz)2, long.u is 1.86BM and when oxidised to M(bz)2 + it has a long.u of 2.95BM
1.95BM gives us n=1 ,, aka one unpaired e-
if a n=1 is oxidised it means u lose an e-,, meaning u now have n=0 REMEMBER THISSS«_space;IF U SEE ANYTHING ABOUT REDOX«_space;DO IT TO THE N VALUE.
for n=1,, fill in the e2, a1 and e1 stuff,, remmeber that its the metallocene atm so u fill the e2 and a1 as if it was degen so for n=1 we get: d1, d5, d7 and d9
then look at all these and oxidise them so now u have, d0, d4, d6 and d9,, and we need it to be diamagnetic so we have the d0 therefore d1 d6 therefore d7
so we have d1 or d7 for the metallocene thing,,
then this changes to an arene,, when the long,u is 1.86bm so n=1,, then this is oxidised to give longu of 2.95BM which is n= 2.
so we need to find the d count that gives n=1
this gives us d1, d3, d5, d7, d9
then thsi is oxidised to give n=2!! so we take an electron away from the e- count,, then see the configs to see which one gives us n=2. this leaves us with d3 or d9
this agrees with the first half and therfore we have cobalt or scandium.
the longu > spin only
so cobalt is more likely to be the answer!!
what does dimagnetic mean
it means the material is repelled from a magnetic field
what does paramagnetic mean
it means the material is attracted to a magnetic field
diamegnetic normally means
rtheres no unpaired e-.
however sometimes it has a n=0 but is still paramagnetic bc of orbital contribution
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