Analyze nanoscale attraction with flexible geometry and constants. Switch units, inspect steps, and save results. Built for clear energy estimates across common interaction cases.
These sample cases show typical magnitudes for different interaction geometries.
| Model | Inputs | Approximate energy | Approximate force or pressure |
|---|---|---|---|
| Pairwise | C = 5 × 10^-77 J·m^6, r = 0.4 nm | -1.220703e-20 J | 1.831055e-10 N |
| Sphere to plate | A = 6 zJ, R = 50 nm, D = 2 nm | -2.500000e-19 J | 1.250000e-10 N |
| Sphere to sphere | A = 8 zJ, R1 = 40 nm, R2 = 60 nm, D = 3 nm | -1.066667e-19 J | 3.555556e-11 N |
| Parallel plates | A = 7 zJ, D = 1.5 nm, Area = 1 µm² | -8.252479e-16 J | 1.100330e+06 Pa |
Pairwise molecular model: U = -C / r6, and |F| = 6C / r7
Sphere to plate model: U = -(A R) / (6D), and |F| = A R / (6D2)
Sphere to sphere model: Reff = (R1R2) / (R1 + R2), U = -(A Reff) / (6D)
Parallel plates model: U / Ap = -A / (12πD2), |P| = A / (6πD3)
These are simplified non-retarded expressions. Real systems may differ because of material layering, roughness, medium effects, retardation, and temperature.
Van der Waals interaction energy describes weak attraction between atoms, molecules, particles, and surfaces. These forces matter when distances become very small. They influence colloids, thin films, powders, coatings, biomaterials, and nanotechnology. A reliable Van der Waals interaction energy calculator helps estimate adhesion trends before experiments. It also supports material screening, surface engineering, and micro or nano device design.
This calculator covers several common interaction models. You can evaluate a pairwise molecular interaction with the constant C and separation distance r. You can also estimate non-retarded energy for a sphere near a plate, two spheres, or two parallel plates with a Hamaker constant. That flexibility makes the tool useful for chemistry, physics, materials science, and surface science workflows.
Unit conversion is built into the form. You can enter distances in meters, millimeters, micrometers, nanometers, or angstroms. Radius and area inputs also support practical nanoscale units. This reduces mistakes during setup. The calculator converts everything to SI units internally. It then returns interaction energy in joules and electron volts, along with an attractive force or pressure when applicable.
The result is shown directly below the header and above the form after submission. That placement makes repeated testing easier. You can compare several geometries quickly. CSV export helps save structured results for reports or spreadsheets. PDF export helps share a clean summary. The example table gives reference values for common nanoscale cases.
The formulas used here are standard simplified expressions for non-retarded Van der Waals attraction. Real systems can deviate because of roughness, medium effects, retardation, temperature, shape irregularity, and layered materials. Even so, these equations are excellent for first-pass estimation. They reveal how strongly energy changes with distance, especially in the pairwise and plate models.
Use this tool when you need fast, transparent, and repeatable calculations. It is helpful for comparing Hamaker constants, testing separation sensitivity, or checking whether attraction may become significant in a design. It can also support education. Students can verify manual calculations and understand scaling laws. Engineers can evaluate contact risk in MEMS, nanoparticle agglomeration, and surface proximity effects during design.
It estimates Van der Waals interaction energy for several simplified geometries. Depending on the selected model, it can also report attractive force, pressure, effective radius, and converted SI inputs.
Use pairwise for atom or molecule style interaction with a C constant. Use sphere-plate for a particle near a flat surface, sphere-sphere for two particles, and plates for two parallel flat surfaces.
The Hamaker constant measures the strength of Van der Waals attraction for bulk bodies. Its value depends on the interacting materials and the medium between them, and it is usually expressed in joules.
A negative interaction energy means the force is attractive and the system becomes more stable as separation decreases. Larger negative magnitude usually indicates stronger attraction under the model assumptions.
No. They are standard simplified formulas for first-pass estimates. Real systems may be affected by retardation, roughness, coatings, geometry deviations, medium changes, and temperature-dependent material properties.
Yes. The calculator converts common distance, radius, and area units into SI values before solving. That makes nanoscale input easier and reduces manual conversion errors.
Van der Waals attraction is highly separation dependent. In the pairwise model, energy scales with one over distance to the sixth power. Small distance changes can therefore produce large output changes.
The export captures the visible result summary. CSV is useful for tabular records, while PDF is helpful for sharing a clean calculation snapshot with colleagues, clients, or students.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.