Electron density is the measure of the probability of an electron being present at an infinitesimal element of space surrounding any given point. According to quantum mechanics, due to the uncertainty principle on an atomic scale, the exact location of an electron cannot be predicted, only the probability of its being at a given position. Electron density *ρ*(r) is a fundamental property of atoms, molecules, and condensed phases of matter. For one-electron systems, the electron density at any point is proportional to the square magnitude of the wavefunction. In quantum chemical calculations, the electron density, *ρ*(r), is a function of the coordinates r, defined so *ρ*(r)dr is the number of electrons in a small volume dr. For closed-shell molecules, *ρ*(r) can be written in terms of a sum of products of basis functions:

### Application

- Properties determination, such as charges, dipoles, and electrostatic interaction energies.
- Computation of infrared intensities and determination of non-covalent interactions.
- Investigation of trace element levels including Cr, Cu, Fe, Mg, Mn, Se, Zn, As, B, Si, and Co in serum samples.

### Our Features

- Machine learning

Machine learning is established on the basis of the wave function and has been developed as a powerful method to predict electron density. We have various quantum computing methods driven by machine learning to perform the prediction of electron density.

- We use Density Functional Theory (DFT) to compute the electronic structure and calculate its characteristics in the field of condensed matter physics. A variety of energy band calculation methods, such as LDA, GGA, meta-GGA, hybrid,
*etc*., are available at Alfa Chemistry. - Coupled Cluster Single-Double and Triple, which is also called CCSD(T), is another machine learning method we applied for the prediction of electron density. And we often apply it in the calculation of some weaker interactions.
- Atomic coordinates

Internal molecular information such as atomic coordinates and atomic numbers can provide valuable references for the measurement of molecular physical and chemical properties. The 3D configuration of atoms determines the properties of the material, offering important electronic-structure data of small molecules and larger compounds. Therefore, we can quantitatively predict the electron energy through the 3D coordinates of all atoms.

### Our Services

Our electron density prediction service requires you to provide specific requirements and the timeline according to your needs. We will provide you with raw data and analysis services as soon as possible.

**Alfa Chemistry can offer you include but not limited to the following,**

**Van der Waals interaction simulation**

We have built a potential model to observe particles based on the van der Waals interaction. At Alfa Chemistry, we apply mathematical functions to model this interaction. In the Van der Waals interaction simulation, our teams calculate the Van der Waals coefficients for atoms and molecules to provide accurate electronic structure calculations.

**X-H, X-Y bonds strength/stability calculation**

Measurement of bonds strength or stability is a method to judge whether the crystal is stable or not. Weak interaction is a common research object of wave function analysis. We analyze the X-H and X-Y bonds and estimate the bond critical point (BCP) properties defined by the atoms-in-molecules theory (electron density, laplace function of electron density, energy density, potential energy density, *etc*.) strength.

**Small molecule drugs crystal structure prediction**

We apply Fukui function, HOMO, LUMO orbital, atomic charging status, electronic gains and losses to study the interaction between drugs and excipients so as to determine the site of action, the size of the action energy, and the spatial binding configuration between the drug and excipients, Prediction and analysis of crystal structure of small-molecule drugs can be achieved.

**π bonds calculation**

According to the distribution of electrons on the molecular orbital, the total energy of the molecule can be calculated. Therefore, we can predict the energy of the electron and calculate the π bond. Moreover, we also provide additional optimization and validation services for the final π bond.

### Our Advantages

Alfa Chemistry provides fast, specialized, high-quality services of electron density prediction at competitive prices for global customers. Personalized and customized service of electron density prediction satisfies innovative scientific study demands. Our clients have direct access to our staff and prompt feedback to their inquiries. If you are interested in our services, please contact us for more details.