Skip to main content
42 votes
Accepted

Gillespie Stochastic Simulation Algorithm

Yes you can. Below is a fairly general, Mathematica-compiled, fast and robust version. Examples 1. Michaelis-Menten kinetics Michaelis-Menten kinetics for enzyme-directed substrate conversion. The ...
István Zachar's user avatar
29 votes
Accepted

visualizing a normal mode vibration of a molecule in mathematica

Using a few undocumented functions that have been discussed here on the stack exchange before, ...
Jason B.'s user avatar
  • 69.7k
18 votes
Accepted

Minimum energy path of a potential energy surface

Smooth Equations Let $\varphi \colon \mathbb{R}^d \to \mathbb{R}$ denote a potential function (e.g., from OP's data file). We attempt to solve the system $$ \left\{ \begin{aligned} \gamma(0) &...
Henrik Schumacher's user avatar
17 votes

What's the principle behind the new MoleculeRecognize function?

Using ResourceFunction["PrintDefinitions"][MoleculeRecognize], one can determine that the source implementation is MolVec. The specific source code is: ...
Carl Lange's user avatar
  • 13.2k
16 votes

Plot 3D model of DNA in Mathematica

Here is a function that can wrap a double helix around any (sufficiently smooth) parameterized curve. Among other things, the function below computes a Bishop frame along the curve; twisting it leads ...
Henrik Schumacher's user avatar
16 votes
Accepted

Chemical data of Lactic acid

I've struggled with How Mathematica expects the end-user to interact with knowledge databases for quite some time. While this solution is likely not universal, it has been reasonably successful for ...
bobthechemist's user avatar
15 votes

ChemistryData — where is specific gravity?

Specific gravity is not on the property list of curated chemical properties, so you can't get it directly. However, here is a function that will compute it. ...
m_goldberg's user avatar
  • 108k
15 votes

Minimum energy path of a potential energy surface

Interesting problem. Decided to treat it as a graph problem, rather than fitting an InterpolatingFunction to it and getting descent directions from there. If I knew ...
MikeY's user avatar
  • 7,203
15 votes
Accepted

Why does `Molecule` return a molecule for an incorrect SMILES string?

This is a bug, the most basic manifestation of which is ...
Jason B.'s user avatar
  • 69.7k
14 votes

Computing the surface area and volume of molecules

I can offer a solution by discretization to ElementMesh with external meshing software Gmsh. Currently it produces better quality mesh on curved surfaces that built-...
Pinti's user avatar
  • 6,523
14 votes

What's the principle behind the new MoleculeRecognize function?

I am one of the authors of Molvec. It was designed in a classical approach using various image processing heuristics to guess the structure. While it's on my todo list, we still haven't published a ...
dkatzel's user avatar
  • 241
14 votes

Mass Transport Model

OK. Let me extend my comments to an answer. First of all, I'd like to point out why OP's attempt doesn't work: "NDSolveValue should return a list with three ...
xzczd's user avatar
  • 67.7k
13 votes
Accepted

Plot polygonal surface

(grabbing a lot of code from this answer) This is just to get you started, adding in colors to the final GraphicsComplex should be pretty easy. ...
Jason B.'s user avatar
  • 69.7k
13 votes

How to apply different equations to different parts of a geometry in PDE?

Denote the disk by $\varOmega$ and its boundary by $\varGamma = \partial \varOmega$. I'd prefer to denote the function residing on the boundary by $u \colon \varGamma \to \mathbb{R}$; the function on ...
Henrik Schumacher's user avatar
13 votes

Computing the surface area and volume of molecules

The paper Fast Calculation of van der Waals Volume as a Sum of Atomic and Bond Contributions and Its Application to Drug Compounds, pointed out by theorist gives an approximate formula for the ...
Jason B.'s user avatar
  • 69.7k
13 votes

MoleculePlot3D - how to replace spheres?

How to replace the spheres in the plot with other 3d figures, say "N" with a Cylinder, "O" with a Cuboid, and "H" with a sphere. This answer takes points from the ...
Anton Antonov's user avatar
12 votes
Accepted

Connectivity in a molecule and permutations

Getting the graph from the XYZ file You have only a set of coordinates and atom types in an XYZ file. When you import it in Mathematica you can import 3 elements: the 3D plot, the coordinates, and ...
Jason B.'s user avatar
  • 69.7k
12 votes
Accepted

Maxwell construction problem with FindRoot

Good job on describing your problem. Copying your definitions from your question ...
Jack LaVigne's user avatar
  • 14.5k
12 votes
Accepted

Molecule fingerprint functions v13

edit: For direct access to the underlying fingerprint functions behind FeatureExtraction for molecules, see the Molecule Fingerprints paclet in the new paclet ...
Jason B.'s user avatar
  • 69.7k
11 votes
Accepted

Proteins, ProteinData, WolframAlpha

Here's a workaround that directly queries the PDB search API and returns the first num search results as a Dataset[]. The ...
J. M.'s missing motivation's user avatar
11 votes
Accepted

ChemicalData returns the correct result for "Sulfuric" but an empty list for "Sulfuric Acid". Why?

Consider using a dedicated search pattern making function. Here is an example. ...
Anton Antonov's user avatar
11 votes

DFT for Helium atom

Here's what I mentioned in the comments. Life is better with NDEigensystem and NDSolve: ...
b3m2a1's user avatar
  • 47k
11 votes
Accepted

How to apply different equations to different parts of a geometry in PDE?

Since I have the code to solve the original problem described in the article GDI-Mediated Cell Polarization in Yeast Provides Precise Spatial and Temporal Control of Cdc42 Signaling, I will give here ...
Alex Trounev's user avatar
  • 47.8k
11 votes

When looking at a chemical's bond lengths, which bonds do they represent?

There must be a better way, but here is a first pass. This method is based on [Experimental] functions, two of which are new in MMA 12, BondList and ...
LouisB's user avatar
  • 12.7k
10 votes

How to apply different equations to different parts of a geometry in PDE?

What about: Noting that equations 1 and 3 form a complete set, and solve them first, treating the remaining equation 2 for m afterwards. Noting that your imposed ...
MK.'s user avatar
  • 341
10 votes
Accepted

Chemical formulas with Mathematica

ClearAll["Global`*"] Assuming that you are starting with a chemical formula ...
Bob Hanlon's user avatar
  • 161k
10 votes
Accepted

MoleculePlot draws sucrose benzoate with overlapping bonds

Mathematica uses a number of libraries for generating 2D structure diagram coordinates. The automatic method produces a suboptimal result for this molecule. Probably the system should try to check ...
Jason B.'s user avatar
  • 69.7k
9 votes

Plot polygonal surface

...
Bob Hanlon's user avatar
  • 161k
9 votes

How to plot Compressibility factor Z vs Pressure P using ParametricPlot?

The plot you were trying to reproduce is a plot of the reduced van der Waals equation; that is, it is using the reduced pressure $P_r=\frac{P}{P_c}$ and reduced temperature $T_r=\frac{T}{T_c}$ as the ...
J. M.'s missing motivation's user avatar
9 votes

Constructing Icosahedral Fullerene Graphs

Jason B gave a hint to the tool buckygen. This tool is easily downloaded, unpacked and compiled (by running make in the unpacked ...
Henrik Schumacher's user avatar

Only top scored, non community-wiki answers of a minimum length are eligible