transition metals

Why are d-block transition elements magnetic?

They have unpaired electrons

Properties of d-block transition elements?

Hard, ductile, malleable

What is a transition metal complex?

A central metal atom/ion surrounded by ligands that bind to the metal through electron donation

What is a coordination complex?

None of the ligands bind through a carbon atom

What is an organometallic complex?

At least one ligand binds through a C atom

How are electrons assigned to atomic orbitals?

• Aufbau principle

• Hund’s rule

• Pauli Exclusion principle

Why are Cr and Cu exceptions?

Extra stability is gained from half or fully filled subshells

What happens when a metal is in a compound (electron configuration)?

The filling order reverts to 3d before 4s

How are electrons removed from orbitals on ionisation?

s electrons are removed before d electrons

Why does ionisation energy increase across the periodic table?

Increasing effective nuclear charge

What is the coordination number?

The number of ligands around a metal

Is the metal a Lewis acid or base?

Is the ligand a Lewis acid or base?

Metal is a Lewis acid as it accepts electrons

Ligand is a Lewis base as it donates electrons

Why are transition metals able to readily form complexes?

They have energetically available empty d orbitals

Why are good bases generally good ligands?

They have an available electron pair

What is the shape of coordination number 6?

Angles?

Octahedral

90º adjacent angles, 180º opposite angles

What are the two shapes for coordination number 4?

Angles?

1. Tetrahedral, 109.5º

2. Square planar, adjacent 90º; opposite 180º

What are ligands?

Electron pair donors

What are monodentate ligands?

Coordinate to a metal through one donor atom

What are polydentate ligands?

Coordinate to a metal through more than one atom

What is a chelate ring?

Two or more donor atoms coordinate to a single metal

What are constitutional/linkage isomers?

Same formula, different atom to atom connectivity

What are stereoisomers?

Same formula, same atom to atom connectivity, different arrangements in space

What are the two types of stereoisomers?

Geometrical isomerism

Optical isomerism

Do tetrahedral complexes form geometric isomers?

No

Do square planar complexes form geometric isomers?

When two ligands are the same

What is the difference between cis and trans isomers?

Cis = identical ligands adjacent to each other, 90º

Trans = identical ligands opposite, 180º

Do octahedral complexes form geometric isomers?

When two or three ligands are the same

What are the differences between fac and mer isomers?

Three identical ligands form a face = facial, 90º

Three identical ligands in plane = meridional, 90º and 180º

How to use triangles to determine fac and mer isomers?

If the triangle goes through the middle, then it is mer

What is optical isomerism?

When an object cannot be superimposed onto its mirror image

What are the optical isomers called?

Enantiomers

Do tetrahedral complexes form optical isomers?

Only if all 4 ligands are different

Do square planar complexes form optical isomers?

No

Do octahedral complexes form optical isomers?

Does not occur with mono dentate

Occurs when there are 2 or 3 bidentate chelating ligands

In an octahedral [MA₂(chelate)₂] complex, which is chiral?

therefore how many isomers does it have?

The cis isomer is chiral and can form optical isomers

It has three isomers

How to name complexes?

Ligands first (in alphabetical order), then metal

How to name a compound (i.e. complex and counter ions)?

Cation first then anion