Coordination Compounds Flashcards
In a coordination complex the transition metals serves as lewis ____ while the ligand as lewis ____
acid (accept electron)
base (donates electron)
The ___ or the primary valence of the metal, expresses the ability of the metal to form ionic compounds with oppositely charged ions
oxidation state
The ___ or secondary valence expresses the ability of the metal to bind to ligands
Coordination number
Refers to the number of times a ligand bonds to a metal through donor atoms
Denticity
Substances that have ability to hold metal atoms like a claw
Chelating agents
High CN is associated with large radii of atom or ion
Low CN is associated with bulky and charged ligands
Recall the three factors that govern the CN of a complex
Isomers the differ in terms of connectivity of atoms
Structural isomers
Recall 5 types of structural isomers
Linkage
Ionization
Hydration
Coordination
Polymerization
Ambidentate ligands give rise to ___ isomerism in which the same ligand may link through different atoms
Linkage
Isomerism that occurs when a ligand and a counterion in one compound exchange places
Ionization
Very similar to ionization but one of the ligands in the complex is water
Hydration
Isomerism that forms when there are different complex ions that can form from the same molecular formula
Coordination
Isomers that denite complexes which have the same empirical formula but different molar masses
Polymerization
Isomers that differ only in their 3D arrangements
Stereoisomers. May be geometric or optical
First anti cancer drug based on in inorganic complexes
Cisplatin
Isomers that are non-superimposable mirror images of each other and can rotate plane-polarized light
Optical isomers
Recall two types of stereoisomers
Recall formula writing and naming
For square planar and octahedral complexes, there are ____ geometric isomers
Cis-trans
Octahedral complexes also have additional geometric isomers except for cis trans including ___
Facial-meridional
An electrostatic model that involves the interactions between ligands and metal d-orbitals, though not taking into account it’s overlap
Crystal Field Theory.
Application of MOT that concentrates on metal d-orbitals providing information on splitting parameter
Ligand field theory
When ligands attach to transition metal, the d-orbitals are split into high and low energy orbitals.
Recall the two eg orbitals, and three t2g orbitals
Refers to the separation between tg and eg orbitals
Ligand field splitting parameters
The magnitude of ligand field splitting parameter depends on charge on the metal ion, principal quantum number of metal, and nature of ligands
Eg orbitals go up in energy by 3/5∆o
T2g orbitals go down in energy by 2/5∆o
Recall the factors that affect the magnitude of ligand field splitting parameters
Recall the spectrochemical series of M+
Increasing the charge on a metal ion
1. Increases the attraction of anionic ligands to the metal
2. Decreases the radius of metal
Conclusion: the magnitude of slitting parameter increases ss the charge on the metal ion increases.
An increase in principal quantum number of the metal means an increase in the radius of the metal, resulting in shorter metal-ligand distances and stronger d-orbital ligand interaction
Conclusion: for complexes with metals and ligand from the same group, the magnitude increases with increasing principal quantum number
For series of chemically similar ligands, the magnitude of splitting increases as size of donor atom decreases.
Spectrochemical series have weak and strong field ligands (higher splitting energy)
For transition metal ions with ___ to ___ configurations exhibit high spin and low spin states.
d4 to d7
Phenomenon that occurs when degenerate orbitals are not equally filled with electron
Jahn-Teller effect
Recall octahedral configurations that doesn’t experience Jahn Teller distortion
d3
high spin d5
low spin d6
d8
d10
Refers to the reduced interelectronic repulsions in the valence orbital of a metal when it’s bonded with ligand in a complex
Nephelauxetic effect
Dimensionless quantity that indicates the degree of attraction of a material in response to an applied magnetic field
Magnetic susceptibility
Positive magnetic susceptibility suggests
Paramagnetic (unpaired)
Negative magnetic susceptibility suggests
Diamagnetic (paired)
Coordination compounds with strongfield ligands are yellow, orange, or red because they absorb ___
Higher energy violet or blue light
Coordination compounds with weak field ligands are blue-green, blue, or indigo because they absorb ___
lower energy yellow, krange or red light
Selection rule that states that only transition between states of different parity are allowed.
Laporte selection rule.
Parity is symmetry with respect to a center of inversion (gerade or ungerade)
Selection rule that states that only transitions between states of the same multiplicity are allowed
Spin selection rules
The d-d transitions are allowed by relaxing the first selection rule through vibronic coupling, temporarily destroying symmetries
Spin orbit coupling may relax the second rule to allow some transitions
Recall naming of complex coordinate compounds
Coordination of a ligand to a metal center via an uninterrupted and contiguous series of atom
Hepaticity
