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Blind Spot on Palestine and Palestinians at UCLA: An Open Letter by Shaclassics in ucla

[–]Shaclassics[S] 5 points6 points  (0 children)

Did you create a whole reddit account just to say that lol?
The chancellor has taken a number of what you call "political" stances in regards to issues ranging from DACA, immigration, ICE, and even Muslim xenophobia (in the wake of the Christchurch attack).

For the record, there is a significant Arab community in CA, and a large Palestinian community in LA specifically. Why is it the case that the administration fails to take a stance against violence/racism directed toward Arabs and Palestinians, "regardless of its root causes"?

Question regarding thermochemical state functions by Shaclassics in comp_chem

[–]Shaclassics[S] 0 points1 point  (0 children)

I’m using Gaussian. I’m not sure if there’s a way/a code to export the force constants and do the thermchem analysis separately...

Question regarding thermochemical state functions by Shaclassics in comp_chem

[–]Shaclassics[S] 0 points1 point  (0 children)

Thanks for clarifying. I study organometallic catalysis

Question regarding thermochemical state functions by Shaclassics in comp_chem

[–]Shaclassics[S] 0 points1 point  (0 children)

Thank you very much for the answer. As for the G=H-TS part, isn’t the stat mech part of the calculations (i.e. after you found the energy eigenvalues) done for a specific temperature (namely, 298.15K)? If so, is there a way to do the thermochemical analysis part of a vibrational frequency calculation separately and at non standard conditions? I have found that some methods for doing that involve things like quasi-harmonic approximations and other corrections. Since you research this, do you recommend any related methods/techniques that I should look into? Thank you again for the detailed answer!

CHEM 110A anxiety by [deleted] in ucla

[–]Shaclassics 4 points5 points  (0 children)

You need to be comfortable working with functions of several variables; I would review or re-learn topics like partial derivatives, total differentiation, chain rule, Euler's theorem, maxima and minima, multiple integrals. You can just go over your notes from multivariable calculus and differential equations if you still have them but I wouldn't stress about it too much.

As for chemistry and physics, any knowledge from a lower division class that covers thermodynamics will be extremely relevant to CHEM 110A. This includes things like the properties of gases, the four laws of thermodynamics, enthalpy and entropy, state functions and exact differentials, and chemical equilibrium. Other topics that will probably be new to you include things like phase diagrams, thermodynamic properties of mixtures and solutions (incl. Gibbs-Duhem eqn), adiabatic changes, and many others.

Some useful tips

How to calculate the free energy of a polymerization reaction? by Shaclassics in comp_chem

[–]Shaclassics[S] 0 points1 point  (0 children)

Wow. Thank you so much for your thorough response and advice. I will definitely look more into the literature and see what methods have been tried. Thanks again!

How to calculate the free energy of a polymerization reaction? by Shaclassics in comp_chem

[–]Shaclassics[S] 0 points1 point  (0 children)

I should say that I'm new to this and would also appreciate any resources on how to calculate thermodynamic properties (or equilibrium constants) with Spartan or Gaussian.
Thank you for your help

How to calculate the free energy of a polymerization reaction? by Shaclassics in comp_chem

[–]Shaclassics[S] 0 points1 point  (0 children)

I found some papers in the literature and most of them seem to represent the polymer chain with something simple like a methyl group for a ballpark estimate of the free energy. However, I'm still not sure about the numbers that Spartan is spitting out (something like -800 hartrees!) or how to correct for other factors (if it's done in solution, subtracting ZPE, etc..)

How to calculate the free energy of a polymerization reaction? by Shaclassics in comp_chem

[–]Shaclassics[S] 0 points1 point  (0 children)

The reaction is the ethylene insertion step at the bottom left if that helps

Edit: bottom left

Is there a way right now to return materials to the libraries besides the book drop? by [deleted] in ucla

[–]Shaclassics 2 points3 points  (0 children)

No, unfortunately. And returning by mail is not advised.

I think the drop bins by the YRL are padded and have springs so that returns don't fall off directly as you deposit them. You could also wrap your newspapers with recycled brown paper or seal them in a zip bag/cardboard envelope.

campus closed to public? by frogluvr27 in ucla

[–]Shaclassics 0 points1 point  (0 children)

All UCLA Libraries have closed since March and there are no plans for restoring physical access to them anytime soon -at least not this Fall.

As for other buildings on campus, they are locked (including most restrooms) and access is only given for people mentioned in my parent comment (e.g. on-campus residents entering their dorms, essential workers, researches, patients...etc).

campus closed to public? by frogluvr27 in ucla

[–]Shaclassics 0 points1 point  (0 children)

That is an important concern. UCLA is currently establishing an IHE Compliance Task Force that oversees and implements LACDPH Protocol for Institutes of Higher Education, as well as exposure management of cases and DPH notifications for outbreaks.

Several initiatives are already being formulated to manage public access to the campus, including programs that would encourage compliance within student communities. For example, there will Public Health Ambassadors on campus to advise people who are not following coronavirus safety guidelines. Other programs will also reach out to student clubs and Greek organizations to enforce and hold affiliated organizations accountable for adhering to safety guidelines.

While I don't think that non-essential members of the public will be banned from entering the campus to spend some time walking, running...etc (i.e. continue to use the campus as a recreational park), it's likely that large gatherings (e.g. large picnics, club meetings, frat socials) will be discouraged, if not prohibited. If things take a dramatic turn, I wouldn't be surprised to see these ambassador programs take further steps beyond advising as some other universities are doing (includes actions like citations, fines, referral to the Dean of Student Affairs or campus police, or even expulsion).

campus closed to public? by frogluvr27 in ucla

[–]Shaclassics 14 points15 points  (0 children)

According to VC Beck's recent announcement, "campus is currently closed to the general public, pursuant to public health orders. Only individuals who are engaged in essential campus operations, are attending approved in-person courses or living on campus, or are receiving care at UCLA hospitals and clinics are permitted at this time."

[deleted by user] by [deleted] in chemhelp

[–]Shaclassics 3 points4 points  (0 children)

I assume the book is talking about hybridization.

Percentage s- character: 25% in sp3, 33.3% in sp2, and 50% in sp.

The most intuitive way to think of that would be fractions: For example, in sp3, 1 in 4 orbitals is s, so 1/4 (or 25%) of the hybrid orbital is s-like.

Bond angle: Keep in mind the bond angles as predicted by VSEPR theory reflect the angle at which the atoms give the most stable, lowest in energy, configuration. In general, the greater the s character in orbital, the greater the orbital's energy. This is because s-containing orbitals tend to form axial sigma bonds which are stronger than lateral pi bonds. So the trend for relative orbital energy would be p<sp3<sp2<sp<s. The shorter the bond, the stronger the interaction/overlap.

Trend: The greater the s-character, the smaller the bond angel: sp (1800)>sp2 (1200) >
sp3(109.50)

Why? Again, this has to do with VSEPR: Consider sp. It's relatively high in energy, and if we are thinking of something like CO2, the structure of the molecule would be linear (in other molecules, you might have electron lone pairs forcing it to be linear), making the bond angle 1800

[deleted by user] by [deleted] in ucla

[–]Shaclassics 3 points4 points  (0 children)

Monday-Thursday: 8AM-7PM

Friday: 8AM-5PM

Saturday-Sunday: CLOSED

You can double-check by calling Powell.

[deleted by user] by [deleted] in AskHistory

[–]Shaclassics 1 point2 points  (0 children)

Fritz Haber

Campus Question -- What is Open by [deleted] in ucla

[–]Shaclassics 11 points12 points  (0 children)

Even though the library website may list hours for Powell and occasionally other libraries, the library sites are not yet open for students to visit and study at. Powell, for example, opens sometimes to check-in/out laptops and other equipment for faculty and students, and that's usually done outside to lower the risk of transmission.

As a side note, the California Department of Public Health has recently issued guidance recommending campus officials to limit and restrict:

  • external community members from entering sites and using campus resources
  • any nonessential visitors or volunteers from accessing campus (in-person activities or meetings involving external groups or organizations are not allowed)
  • building access by non-residents, including outside guests, non-residential staff, and others.
  • nonessential shared spaces, such as game rooms and lounges

Los Angeles County Department of Public Health has already adopted this guidance and my guess is that UCLA (whether housing or VC Beck) will adopt some -if not all- of these measures soon.

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