Cody Aldaz
  • Member for 5 years, 11 months
  • Last seen more than a month ago
  • Ann Arbor, MI, United States
Visible Light Spectrophotometer Recommendations
8 votes

Disclaimer: I'm not affiliated with any company However, Ocean Optics cuvette spectrophotometers are a good choice This model is used in some undergraduate labs and is good because the cuvette ...

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Particle in a box with different barriers between two molecules
Accepted answer
6 votes

for the infinite barrier I'd put an electron on just one side of the box with length L/2, meaning that electron is trapped on one side/face of the ammonia. For the no barrier part treat the electron ...

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Why is chemical accuracy defined as 1 kcal/mol?
5 votes

Certainly experimental accuracy is a major factor. However, another argument for this rule of thumb is that at room temperature, a difference in free energy of 1.4 kca/mol results in a equilibrium/...

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How to properly model a mechanochemical reaction of barium titanate and copper(II) complexes?
5 votes

Reaction rates can be calculated from the Arrhenius equation $k=Ae^{E_a/RT}$ where $E_a$ is the activation energy found at the transition state. Please check out the Reference 1 for calculating ...

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Are there any molecular modeling programs that can build materials made up of three or more elements into a cylindrical shape?
5 votes

Various custom software exists to create nanotubes. The following appears suitable: http://www.jcrystal.com/products/wincnt/ A Wolfram Demonstrations application may also be of some use: https://...

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Transition state optimisation on the surface of periclase
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4 votes

To study surface reactions I recommend the growing string method (GSM) for surfaces. Here is a nice quote from the paper which developed it (Ref. 1) GSM’s efficacy was confirmed by comparison with ...

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Vibrational state dependency of the reaction cross section
3 votes

Vibrations are very important for reactions. In the particular example of $\ce{H2+(g) + He}$ vibrational levels 0-3 have an energy less than E0 (minimum energy for reaction), so additional ...

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Conversion of Hessian from internal coordinates to cartesian coordinates
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3 votes

In the Geometric [1] package, there is code to convert an internal coordinate Hessian into Cartesian coordinates def calcHessCart(self, xyz, gradq, hessq): """ Compute the ...

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Is it reasonable to use natural orbitals of an unrestricted HF calculation as a basis to start a CASSCF calculation for a radical
2 votes

Hartree-Fock Orbitals are Always the Wrong Choice for CAS Calculations In Hartree-Fock (HF) theory, only the occupied orbitals contribute to the electronic energy. Due to the presence of Fock exchange,...

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how much baking soda and vinegar will you need to fully fill a ziplock bag up without popping it?
2 votes

Assuming the water doesn't displace much volume in the bag, the volume a mole of CO2 displaces at room temperatre is 22 L. pV=nRT p=1 atm T=298 K R=0.0821 $\frac{L*atm}{mol K}$ Step 1: find out ...

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Expectation value of an observable in quantum system
2 votes

Roughly, the significance is that before measurement the system can be in a superposition of states, the wavefunction of which can be represented by a linear combination of the individual ...

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Help with molecular dynamics and computational modelling to check validity of hypothesis regarding SN2 reaction mechanisms
2 votes

Your hypothesis concerning a "bouncing" contribution to the reaction kinetics would be incredibly difficult to observe or quantify even with the best supercomputers. The likelihood of a molecule to ...

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How to access implicit bond angles that don't appear in Gaussian's z-matrix input?
2 votes

You can reorder the Z-matrix with a free program like Molden. For example open the molecule in Molden and press the ZMat editor. From there you should see a button that says reorder Z-matrix. Click ...

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How to modify viscosity of ZnO ink?
1 votes

Regular black ink is pretty viscous it has a dynamic viscosity ($\eta$) of 4.177. In comparison a 50% mixture of methanol and glycerol has a viscosity of 5.8 Some other solvents to consider are ...

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When are transition state's energy barrier "reasonable" at a certain temperature?
1 votes

Using this website, input the activation energy and temperature and it gives half life. A reasonable half-life is up to the user, but more than 1 day is going to be super slow. Usually assume the ...

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Molecular antibonding orbitals energy
1 votes

Energy is not stored in the energy levels themselves but in the states which occupy them. At normal room temperature the bonding orbitals are occupied according to Maxwell-Boltzmann's statistics $P_i ...

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