lecture 9🅱️

Question 1

whats MO

Answer 1

metal oxide

Question 2

delta H lat is what when it comes to metal oxides

Answer 2

delta H lat is the lattice enthalpy

M2+ (g) + O2- (g) –> MO(s)

Question 3

1st row MO have what structure

Answer 3

they have NaCl structure

a salt structure

Oh around the metal

Question 4

what coordination geom does NaCl have around the Metal

Answer 4

Oh coordination around the Metal.

Question 5

what is Oh

Answer 5

octahedral

Question 6

what is the total magnetic moment made up of

Answer 6

spin motion (s and S)

angular motion (l+L)

Question 7

what gives free atoms // ions magnetism

Answer 7

the spin and angular motion

Question 8

quantum numbers for spin motion

Answer 8

s and S

Question 9

quantum number for angular motion

Answer 9

l and L

Question 10

what is the magnetic moment

Answer 10

the number of unpaired electrons there is per mole.
long u.eff

Question 11

what does knowing the number of unpaired electrons help us know

Answer 11

spin state
coordination geometry
oxidation state

Question 12

explain weak field

Answer 12

high spin
small splitting

when delta o < P

Question 13

what is S

Answer 13

S is total spin

Question 14

how do we find S value

Answer 14

number of unpaired electrons x (1/2)

bc spin of an e- is 1/2

Question 15

whats long U.so

Answer 15

this is the spin only magnetic moment

Question 16

equation to find u.so aka spin only magnetic moment and what does each letter mean

Answer 16

g root S(S+1)

g = gyromagnetic ratio of one e-

S = total spin (number of unpaired e- x 1/2)

Question 17

what do we normally set g: the gyromagnetic ratio of an e- in the spin only magnetic moment equation to

Answer 17

we set it to 2

so we get 2 root S(S+1) for the spin only magentic number value.

Question 18

whats the spin only magnetic moment for smt that is high spin d6

Answer 18

number of unpaired e- = 4
S = 4 x 1/2
S = 2

u.so = g root 2(2+1)
= 2 root 2(2+1)
= 4.9BM (bohr magnetrons)

Question 19

when is the spin only magnetic moment a good approx

Answer 19

when ur applying it to some first row transition elements,, not to all of them

Question 20

which ions have no 1st order orbital contribution,, (spin only magnetic moment) and why

Answer 20

ions with A or E ground terms

bc their higher energy T twrms can mix + contribute

D –> E+T
F –> T+T+A

Question 21

how do we figure out which term an ion is

Answer 21

we look at the electron config (the t2g // eg version) of its ground state and see how many equivalent ways there is to draw each one

aka if theres a d1 ion,, theres 3 t2g’s,, and the 1e- ,, if in its ground state,, can go into either one of the 3 t2g’s

so bc theres 3 different options,, we say it is the T term,, and that its triply degenerate

Question 22

whats an T term

Answer 22

the e- can go in 3 diff degenerate orbitals.

its equally likely to go into any of them

Question 23

whats an A term

Answer 23

when theres just 1 degenerate way of filling in the e- config

Question 24

whats an E term

Answer 24

when theres 2 different ways of drawing the electrons config.

aka high spin d4 (bc theres 2 eg’s it can go into)

Question 25

T

Answer 25

triply degenerate 2 degenerate ways

Question 26

A

Answer 26

1 way singly degenerate or non degenerate

Question 27

E

Answer 27

doubly degenerate 2 degenerate ways

Question 28

what ground state terms will we observe the spin only magnetic moment

Answer 28

the A and E terms will let us observe spin only magnetic moments.

Question 29

what is present in some T term ions

Answer 29

sometimes there is some obrital contribution present this means the e- will orbit the metal nuc

Question 30

which ground terms have an orbital contribution

Answer 30

those that are T term,, aka triply degenerate

Question 31

what do T terms show in tetrahedral molecules,, Td

Answer 31

they show temperature dependant paramagnetism

Question 32

what is L

Answer 32

the total orbital angular momentum

Question 33

how can L aka orbital angular momentum be reduced // quenched

Answer 33

by applying a ligand field to it

Question 34

where does the spin only formula work well for

Answer 34

it works well for the 1st row of transition elements,, doesnt work as wel lfor the 2nd and 3rd ones.

Question 35

which orbitals interact very weakly to the applied ligand field

Answer 35

F orbitals,, aka the F block orbitals interact very weakly with the ligand field

Question 36

if the f obritals barely interact with the ligand field,, what does that mean about its orbital angular moment

Answer 36

it means that it is basically unquenched. bc if its not interacting with the ligand field,, its not being reduced,, so its remaining the same.

Question 37

magnetic moment for spin and anfgular momentum

Answer 37

U.S+L = root 4S(S+1) + L(L+1)

Question 38

geomteries with lower symmetry include what geom

Answer 38

tetrahedral geometries such as Td geometries

Question 39

what bonding can we not separate in Td

Answer 39

we cant separate sigma and pi bonding

Question 40

why is there no g subscript in Td energy levels

Answer 40

bc they have no inversion centre theres no gerade aka symmetric element. phases chnage when u go across the molecule.

Question 41

what bonding is important in Td complexes

Answer 41

pi bonding is very important in Td complexes.

Question 42

delta T is smaller or larger than delta O

Answer 42

its smaller,, its 4/9 smaller than delta O

Question 43

why is delta T splitting less than delta O splitting

Answer 43

bc theres less ligands bonded to the metal and its geometry is different

Question 44

larger delta T values give rise to what geometry

Answer 44

they give rise to trigonal planar geometry.

Question 45

to go from octahedral to trigonal bipyramidal,, what must happen

Answer 45

u most lose a ligand. to go from 6 to 5 of them

Question 46

describe the trigonal bipyramidal structure

Answer 46

dz^2: points at all ligands meaning its extremely high in energy and antibonding dxy, dx^2-dy^2 : middle energy,, points at 1 ligand each: non bonding? dxz, dyz : least amount of energy,, not pointing at any ligands,, bonding

Question 47

describe trigonal bipyramidal based on the dz^2 orbital

Answer 47

its the metal basically,, u have the donut and the 2 lobes coming out of it. and the 2 lobes and donut are diff phases and count as the metal. then theres 5 ligands pointing out of it in their normal trigonal bipyramidal way.