- #1

ReidMerrill

- 68

- 2

## Homework Statement

I'm am trying to find out the magnetic susceptibility,X

_{M}in order to calculate the number of unpaired electrons in Mn(acac)

_{3}via the Evans Method

## Homework Equations

X

_{M}= (477) Δv/(Qv

_{1}C)

X

_{M}= X'

_{m}+ X

_{M}(metal)+ X

_{M}(ligands)

Where X'

_{M}is the magnetic susceptibilty of just the unpaired electrons.

**Δ**v is the frequency difference between the two chloroform peaks, 648.2 MHz (7.2722 ppm-5.6517 ppm)*400 MHz

Q=2 because a superconducting NMR was used

v

_{1}is the frequency of the NMR, 400MHz

and c is the molarity of the solution used, 0.0948M

X'

_{M}T=(1/8)n(n+2) where n is number of unpaired electrons

## The Attempt at a Solution

The X

_{M}I calculated is 4179.1878. I have nothing to base the accuracy of this off of.

the X

_{M}(metal) = 511. THis was for elemental Mn. I couldn't find anything for Mn(III) so this might be the problem. And from the lab manual the X

_{M}(ligands) is 3*52

Solving for X'

_{M}I got 3512.1878

This gives an unpaired electron count of of nearly 3,000 so this cannot be correct.

Any help is greatly appreciated.