Questions tagged [orbitals]
An orbital is a one-electron wavefunction, usually derived by solving the Schrodinger equation. This tag applies to questions about all forms of orbitals; additionally, questions about the construction and properties of molecular orbitals should be tagged with [molecular-orbital-theory].
652
questions
-1
votes
0
answers
28
views
why does sp mixing occur in smaller elements?
So I just started learning MO theory. I'm aware of a difference in the MO energy diagrams for elements smaller than n=14.
The sources I refer all point to s-p mixing in the smaller elements which ...
-1
votes
0
answers
32
views
Which half filled orbital is more stable s or p?
Which of the following elements will have the lowest electron affinity?
(a) $1s^2 2s^2 2p^3$
(b) $1s^2 2s^1$
I came across this question while studying electron affinity. My initial guess was that ...
1
vote
1
answer
62
views
Crystal Field Theory, in a tetrahedral complex, why would $d_{z^2}$ and $d_{x^2-y^2}$ be degenerated ? In terms of counting of repulsion
In Crystal Field Theory, for a tetrahedral (metallic) complex, shouldn't the $d_{z^2}$ and the $d_{x^2 - y^2}$ have different energies, since the repulsion between one lobe and ligands happens $2$ ...
- 257
2
votes
3
answers
981
views
Why only Balmer series of hydrogen spectrum is visible? [closed]
When I was reading about the hydrogen spectrum, I came across the statement:
Only Balmer series of hydrogen spectrum can be visible to our eyes.
I really got surprised by that. Why can't other ...
- 211
2
votes
1
answer
210
views
Why d orbitals oriented along $z^2$ axis assigned zero magnetic quantum number?
I have been studying quantum mechanics recently and I have come across this:
d orbitals oriented along the $z^2$ axis is assigned zero magnetic quantum number
I am wondering why specifically the $dz^...
- 211
3
votes
2
answers
145
views
Why does the ionisation energy of an electron depend only on n and l, when the electron Z(eff) is dependent on the four quantum numbers?
I am a bit confused by the classnotes of MIT.
It says that the binding energy of an electron (in a multi electronic atom) depends on $n$ and on $l$. Especially it says:
$$ E_{n,l} = -E_{I;n,l} = -\...
- 257
1
vote
1
answer
62
views
Atomic radius decreasing across a Periodic Table row - does the RPD of an orbital change depending of the element considered?
I have a concern regarding the RPD of an orbital. Does the RPD of an orbital depend on the $Z$ (i.e. on the element under consideration) ? Especially, can the RPD of an orbital "shrink" to ...
- 257
0
votes
1
answer
54
views
Based on RPDs, how to tell which orbital ($2s$ vs $2p$ or $4s$ vs $3d$) is more stable ? How reliable is the "less shielded" argument? [duplicate]
Professor (from MIT $5.111$ class) argues that $E_{2s} < E_{2p}$ by just saying that, due to the little bump of $2s$ (on the left of its RPD graph), $2s$ is less shielded and, hence, has lower ...
- 257
2
votes
0
answers
33
views
Is the $2p$ RPD defined along the z-axis?
In MIT $5.111$ class (lecture $6$), we are to compare the most probable radius of a $2s$ orbital and a $2p$ orbital. The graph used by the professor represents the RPD versus $r$:
My question is: in ...
- 257
1
vote
0
answers
68
views
In the RDF plot of a particular orbital, why don't peaks come with radius greater than that of the max peak?
While studying radial distribution function (RDF) plots I see that orbitals (3s, 2s, ... 3p etc) often have peaks at radii less than that of the maximum peak. Assuming the probability of finding an e-...
2
votes
0
answers
34
views
Nonplanar polarization in allenes and aromatic compounds
I recently came across this elaborate article on electrophilic aromatic subsitution.
In the third chapter "General mechanistic considerations in electrophilic aromatic substitution" the ...
- 567
0
votes
0
answers
35
views
What's the most up to date explanation for the stability of high multiplicity states?
"However, accurate quantum-mechanical calculations (starting in the 1970s)... singly occupied orbitals are less effectively screened or shielded from the nucleus, so that such orbitals contract ...
user146362
2
votes
0
answers
150
views
Do any molecules contain a phi bond?
In chemistry, phi bonds (φ bonds) are covalent chemical bonds, where six lobes of one involved atomic orbital overlap six lobes of the other involved atomic orbital. I researched this question a lot; ...
user145192
-1
votes
1
answer
80
views
Degeneracy of Orbitals
(Sorry, in advance if my question is silly or low quality but I want to ask this to someone.)
When an electron enters an orbital, it should technically have an electric Field and also magnetic field(...
- 107
0
votes
0
answers
34
views
Why should higher energy empty orbitals be chosen over lower energy empty orbitals during hybridisation?
Organic chemistry by jonathan clayden states during his explanation of hybridisation using trigonal boron structure (sp2) and tetrahedral boron structure (sp3):
You want to populate the lowest energy ...
- 17
0
votes
1
answer
80
views
On the relativistic contraction of orbitals
In Platinum $\text{Pt}$, why do $\text{s}$ and $\text{p}$ orbitals contract when electrons start travelling at relativistic speeds $|v|\sim c$, while $\text{d}$ orbital expands?
The way I reasoned ...
- 159
2
votes
1
answer
82
views
Where are the electrons located when two atomic orbitals overlap? (VBT)
According to the valence bond theory(VBT), a covalent bond is formed by the overlapping of atomic orbitals containing electrons of opposite spin which pair together. However what is the physical ...
- 77
4
votes
0
answers
100
views
The sign of the lobes in an atomic orbital
In atomic orbital diagram of an atomic orbital, the lobes are represented as either positive or negative. It is said that the wave function is 'positive' where the lobe is depicted positive and '...
- 77
1
vote
0
answers
61
views
Carbonyl and thiocarbonyl 13C NMR
According to this paper, the deshielding effect of C=S group is specifically due to the delta(11), which is the least shielded component. However, the conclusion tells me that this component is ...
user139387
2
votes
0
answers
57
views
1,3-butadiene conformation difference [duplicate]
I am aware that there are 2 well-known conformations of 1,3-butadiene which is s-cis and s-trans conformation.
The s-trans conformation is clearly more stable than the s-cis conformation whose ...
user139387
2
votes
0
answers
80
views
Do d-orbital electrons shield each other or not?
"The shielding of one 4f electron by another is less than that of one d electron by another, and as the nuclear charge increases along the series, there is fairly regular decrease in the size of ...
- 29
0
votes
0
answers
41
views
How does more s character shorten bonds and strengthen bonds?
I'm aware that having more s character means that electrons are in the lowest energy state (?) and very close to the positive atomic nucleus. But then what’s the connection between having electrons ...
- 11
1
vote
1
answer
94
views
Is the energy difference between the 2s and 2p orbital smaller than the difference between 3s and 3p?
on this website (https://physics.nist.gov/PhysRefData/ASD/levels_form.html), you can look up atomic spectra. For example, if you query "Na I", you will see that the Level (cm^-1) for the ...
- 13
-3
votes
2
answers
75
views
Lewis dot structure vs orbitals
I am currently teaching myself AP Chemistry, so am at a very basic level still.
I am studying chemical bonds now, but am wondering why the orbitals don't make a difference to the way atoms bond.
To ...
- 103
1
vote
1
answer
107
views
How did scientists prove that electron configuration was true if we do not know exactly where electrons are? [closed]
In Wikipedia, there is an entry for electron configurations
which explains all about them, but I did not find from this article how they were discovered. If we take into account Schrodinger's quantum ...
- 803
0
votes
0
answers
77
views
Why is Sulfur Trioxide has SP² hybridization? [duplicate]
When I google what is the type of hybridization in SO₃ it gives me "SP² hybridization". The problem I have is why does it has the above hybridization when it has 3 double bonds with the ...
- 439
-2
votes
1
answer
76
views
Why does the two OH bonds in H2O have different bond disassociation enthalpies? How does the bond cleavage happen here?
I came across this question, and in the text it was written as 'change in the chemical environment'. I wasn't satisfied with this explanation, so I am looking for a more detailed answer on this matter ...
-3
votes
1
answer
72
views
How does the concept of the electron shell (also called energy level) and the orbital coexist? [closed]
Running into a bit of confusion trying to understand the atomic structure and the root cause is mostly related to orbitals and energy levels.
At a basic level, I was taught that electrons orbit the ...
- 5
-1
votes
1
answer
205
views
Why can s and p orbitals of one atom form hybrid orbitals but the overlaping of s & p orbitals of two different atoms don't form a molecular orbital?
So my question is in the title : Why can s and p orbitals of one atom form hybrid orbitals but the overlapping of one s orbital and one p orbital (perpendicular to the bond axis) of two different ...
- 69
0
votes
0
answers
41
views
Do the paired electrons of subshells' degenerate orbitals contribute to the total exchange energy?
For instance, in d7, there are 5 electrons with the same spin, and 2 electron with the opposite spin, meaning that there are only 3 unpaired electrons. So, which of these would be correct?
(i) Total ...
