# Tag Info

Accepted

### Choice of coordinate system for geometry optimization

You may want to have a look at this paper: "Geometry optimization made simple with translation and rotation coordinates" https://aip.scitation.org/doi/10.1063/1.4952956 This is not a ...
• 8,036

### How to calculate the computational time required for a MD simulation

The simulation speed and efficiency depends on the hardware and software that you use. Things that you should keep in mind are, Every computer is unique in its ability. So only someone with access to ...
• 2,538

### Benchmark Timings of Machine Learning Potentials vs Molecular Mechanics Force Fields

We performed some timing benchmarks as part of our recent paper, albeit not on molecular dynamics: "Assessing conformer energies using electronic structure and machine learning methods" Int ...
• 7,908

### How to calculate the computational time required for a MD simulation

Short answer: Do a short test run for performance estimates. Once you're familiar with a specific hardware/software combination, you may be able to estimate based on the size of the system, but the ...
• 1,947

### What's the best way to compare two DFT codes?

There are many options to answer your question. Just to compare the computation time, the first condition is to run the simulations with the same hardware i.e. in the same system (two different set-...
• 19.9k
Accepted

### Which software is good with generally contracted basis sets?

General vs segmented contraction Unless one is using a fully decontracted a.k.a "primitive" basis set, one uses contracted Gaussian-type orbitals (cGTOs), which are given as a linear ...
• 15.7k

### Which software is good with generally contracted basis sets?

Integral Screening It is possible to place upper bounds on integrals based on the Cauchy-Schwartz inequality: $$\left( a a | b b \right) \ge \left( a c | b d \right)$$ If the first integral is ...
• 1,603

### What's the best way to compare two DFT codes?

What's the best way to compare two DFT codes? I assume here the DFT means Kohn-Sham density functional theory (KS-DFT). The central task of KS-DFT is to solve the following Kohn-Sham equation (atomic ...
• 14.3k

### Which software is good with generally contracted basis sets?

MOLPRO Continuing Susi's excellent benchmarking for $\ce{Zn}$ and $\ce{Zn_2}$, MOLPRO 2012 gives for $\ce{Zn}$: ...
• 29.7k
I don't know for certain, but a fairly general model of the time taken $T(N)$ for a parallel calculation on $N$ processes is, $T(N) = S + \frac{P}{N} + C(N-1)$ where $S\geq 0$ is the serial part of ...