Topic 1 Flashcards
(75 cards)
1
Q
Coordination complex
A
metal bound to several ligands (might be N, P, O, F, S, Cl)
2
Q
Organometallic complex
A
metal and carbon, include ferrocene, n-butyllithium, Cr(CO6)
3
Q
cluster
A
10-1000 atoms of metal and ligands bound together
4
Q
nanoparticles
A
3-100 nm particles used in catalysis. include PbS quantum dots, silver nanoprisms
5
Q
solid state materials
A
3D arrays, structures that exist in nature like silicon
6
Q
eV
A
electron volts
7
Q
Balmer equation
A
1885, describes spectrum of H where energy levels go from n to 2. E = Rh((1/2^2)-(1/n^2)) where Rh = 13.6 eV and n = 3,4,5,6
8
Q
Bohrs quantum theory of atoms
A
1913, energy is emitted during transition btwn orbitals
9
Q
Lyman series
A
energy levels of electrons all drop to 1 in spectrum (in UV range)
10
Q
Paschen transition
A
energy levels of electrons move down to level 3 (emission is in IR region)
11
Q
de Broglie discovery
A
particle wave duality of e-, 1920s. their movement.. lambda = h/p where h is Plancks constant, p = mv
12
Q
Planck’s constant
A
6.626x10-34 J*s
13
Q
Heisenberg and Schrodingers equations
A
1926/27, Heisenberg had a matrix and Schrodinger a ddx for explaining e- wave mechanics
14
Q
1D orbit Schrodinger equation
A
psi’‘(x)=-((8(pi^2)m)/(h^2))(E*Psi)
15
Q
rules for realistic solutions to the wave function
A
- each position on the 1D line has 1 associated probability
- psi’(x) must be continuous
- as x>infinity, prob. approaches 0
- P = 1 for finding the particle if integrating over all of space
- Any solution to Psia and imaginary Psib are orthogonal (their product integrates to 0)
16
Q
n
A
principle QN, tells energy of orbital. can be 1, 2, 3, 4, …
17
Q
l
A
angular momentum, shape of orbital, can be 0, 1, 2, .. n-1. 0=s, 1=p, 2=d, 3=f
18
Q
ml
A
magnetic qn, can be +-0, +-1, +-2 … +-l, determines orientation
19
Q
p orbital orientation
A
2Px, 2Py, 2Pz
20
Q
d orbital orientations
A
dz^2, dxz, dyz, d(x^2-y^2), dxy
21
Q
ms
A
spin quantum number, can be +-(1/2)
22
Q
radial node
A
change in charge radially, # = n-l-1
23
Q
angular node
A
line/cone where charge shifts, # = l
24
Q
aufbau principle
A
fill in orbitals starting at 1s and ascending in energy
25
pauli exclusion principle
each orbital must have e- with opposite spins
26
hund's rule
maximize spin multiplicity, 1 e- per orbital when filling up
27
degenerate orbitals
orbitals with the same energy
28
which orbitals mainly determine reactivity
d and s
29
penetration
how much e- interact with the nucleus compared to other e- with same n
30
exchange energy
how many times we can exchange e- with parallel spin for a set of degenerate orbitals (=K<0) and also pi(e)
31
Coulombic energy of repulsion
1 C (pi(c)) for each pair of electrons in an orbital (with opposite spins) C > 0
32
delta E and P
change in energy between orbitals based on their diff in energy (delta E) and the pairing energy (coulombic minus exchange). if P>E, they will move up, if not a new e- will just pair with existing.
33
shielding
e- closer to the nu take on more attraction and shield further out e- from this
34
Zeff
effective nuclear charge = z (atomic #) - s (shielding constant)
35
Slaters rules
help us determine s (shielding constant)
1. order electron structure with n's of same value together
2. only electrons closer to core than e- of interest are counted
3. (if e- is s or p): same n is 0.35 UNLESS it is 1s, then it's 0.30, n-1 is 0.85, and further is 1.
4. (if e- is d or f) same n is 0.35 and further is 1.
36
ionization energy trends
inc. during p-orbitals, drops at s, rises slowly due to diffuse d-orbital, and overall rises over the period (e- get closer to a larger Nu). spikes when shells are full or half-full. decreases down a group due to shielding
37
ionization energy
represented by delta u, how much energy is needed to remove an e-. 2nd ie is higher than the 1st. helps us estimate the location of an orbital in an atom
38
e- affinity (EA)
the ability of a neutral atom to pick up an e-. DROPS at noble gases (high at halogens), drops for nd10 as well due to full orbital.
39
energetics of adding/removing e-
if one state requires energy (ie adding an e-), the loss will release energy. also, adding an e- to a negative ion takes energy due to the repulsion
40
covalent/ionic radius trends
decreases over period due to inc. nuclear charge, inc. down groups due to nu size. removing e- causes radius to shrink = "additional charge effect"
41
valence e- are
whatever e- are added after the closest noble gas in e- config
42
simple bonding theory
uses lewis dot and vsepr
43
formal charge
nuclear charge - # of bonds - # lp
44
VSEPR
valence shell e- pair repulsion. uses AXmEn where A is center atom, Xm is bonding atom, and En is lone pairs.
m + n = steric number. (bonds + lp)
45
VSEPR steric numbers and shapes (ideal)
2 = linear, 3 = trigonal planar, 4 = tetrahedral, 5 = trigonal bipyramidal, 6 = octahedral, 7 = pentagonal bipyramidal, 8 = square antiprismatic
46
things with more repulsion than normal bonds
(in order of most to least) lone pairs, triple bonds, double bonds
47
bond length axial vs equitorial
axial feels slightly more repulsion so the bonds will be longer
48
electronegativity definition and bond angles
1930, linus pauling. uses pauling units, shows how much affinity for e- an element has. for bonded atoms, a larger electronegativity causes an dec in angle. for central atoms, it increases the bond angle of less electroneg things bound to it (closer held, so more repulsion)
49
polarity and bond angles
polarity also determines where e- want to go, so reduces or inc repulsion at certain places to inform bond angle
50
platonic solids
high symmetry, identical faces. = tetrahedron, cube, octahedron, dodecahedron, icosahedron
51
symmetry elements
mirror plane (sigma), rotation axes (C), inversion center (i)
52
symmetry operations
identity (E), reflection (sigma), rotation (C), inversion (i), reflection-rotation (S)
53
identity operation
E. every molecule has this
54
rotation operation
Cn. what axis (180/n) with the highest n can this be rotated around and be symmetrical? highest n = principle rotation axis. (each time it rotates counts as an operation, ie 3 for C3)
55
reflection operation
sigma. planes of symmetry. in line with principle rotation axis = sigma(v), perp to Cn = sigma(h), and if it bisects 2 C2 axes but is parallel to Cn it is called sigma d.
56
inversion operation
only 1 i (inversion center) on a molecule. all points flip x,y. only squares/rectangles have this.
57
rotation-reflection operation
represented as Sn where it is a rotation around 360/n and then a reflection perpendicular to the rotation axis to get symmetry. n cannot = 1 or 2 (S2 is just inversion)
58
point group
category that represents which symmetry operations a molecule has
59
low symmetry point groups
C1 (only E - most chiral molecules), Cs (only 1 mirror plane - bilateral symmetry), Ci (only inversion point)
60
high symmetry molecules means
there are multiple axes with the principle rotation number (Cn)
61
high symmetry point groups
C infinity v point group = molecule with infinite rotation on a C axis (any position is symmetrical) and infinite mirror planes parallel to it ie. HCl
D infinity h point group - same thing but also has an inversion center (3 atoms in a line usually) ie. OCO
others are platonic solid shaped..
Td = anything tetrahedral, 24 SOs
Oh = anything octohedral, 48 SOs
Ih = icosahedral (like C60), 120 SOs
62
D point groups
have Cn parallel to a C2 axis
Dnh - have a perp. mirror plane (sigma h), are prisms
Dnd - have a sigma d mirror plane. antiprismatic (staggered) molecules
Dn - no mirror planes = propeller
63
C point groups
Have a Cn
Cnv have sigma v - pyramid
Cnh have sigma h (usually in the plane)
Cn only has Cn
S2n has a rotation reflection
64
procedure for determining point group
1. look for Cn (if none find other things)
2. look for a perp C2
3. look for a sigma h
4. look for a parallel sigma or S2n
65
radial wave functions of ns
1s: decay, very rapid.
2s: decay, drops below 0 and asymptote from negative approaching 0.
3s: decay, below 0 then above and approaches 0 (even flatter)
66
probability functions of ns
1s: very high and narrow peak
2s: very small, hits 0, then rmax
3s: very small, hits 0, bigger, hits 0, rmax (very diffuse)
67
radial wave functions of np
2p: small peak and then approaching 0
3p: small peak, goes - and then comes up to approach 0
68
probability functions of np
2p: medium peak (same as 2s but to the left and a single peak)
3p: small peak and a larger more diffuse one (same as 3s but to the left)
69
radial wave functions of nd
3d: one very flat diffuse peak
70
probability functions of nd
3d: flat peak that looks like the largest in 3s or 3p but closer to the left
71
how does orbital change with n
gets larger, more diffuse (pairing energy destabilizes it less)
72
what mainly determines bond angle in a molecule
lone pairs!!
73
why do s orbitals fill in despite the graph
the smaller lobes demonstrate penetration - closeness to nu and fill in first despite rmax being further
74
Cn is also..
the z axis
75
sigma v axes vs sigma d
sigma d happens when molecules have more symmetry, // to the Cn and go BETWEEN atoms while sigma v go through them.
