Converters & Calculators
Dielectric Constant: Common Materials And Solutions
Dielectric Constant of Common Materials
|
Material |
Dielectric Constant |
|
Air |
1.00058986 ± 0.00000050 |
|
Ammonia |
26, 22, 20, 17 (-80, -40, 0, +20 °C) |
|
Calcium Copper Titanate |
>250 000 |
|
Carbon Disulphide |
2.6 |
|
Concrete |
4.5 |
|
Conjugated Polymers |
1.8–6 to 100 000 |
|
Diamond |
5.5–10 |
|
Electroactive Polymers |
2–12 |
|
Ethylene Glycol |
37 |
|
12.4 |
|
|
10–15 |
|
|
158.0–2.3 (0–21 °C) |
|
|
175, 134, 111, 83.6 |
|
|
Hydrogen Superoxide |
128 aqueous –60 |
|
Melamine Resin |
7.2–8.4 |
|
Methanol |
30 |
|
Mica |
3–6 |
|
Natural Rubber |
7 |
|
Paper, Printing |
1.4 (200 kHz) |
|
Polyethylene/XLPE |
2.25 |
|
2.1 |
|
|
Pyrex (Glass) |
4.7 (3.7–10) |
|
Salt |
3–15 |
|
Sapphire |
8.9–11.1 (anisotropic) |
|
11.68 |
|
|
Silicon Dioxide |
3.9 |
|
7–8 (polycrystalline, 1 MHz) |
|
|
Silicone Rubber |
2.9–4 |
|
Sulphuric Acid |
84–100 (20–25 °C) |
|
Vacuum |
1 |
|
Water |
87.9, 80.2, 55.5 |
Note: The dielectric constants listed above were measured at room temperature under 1 kHz. [1]
Dielectric Constant of Common Solvents
|
Solvent |
Dielectric Constant |
Temperature |
|
Acetal |
3.7 – 3.9 |
298 K (25 °C) |
|
Acetic Acid |
6.2 |
293 K (20 °C) |
|
Acetone |
20.7 |
298 K (25 °C) |
|
Acetonitrile |
37.5 |
293 K (20 °C) |
|
Acrylate |
2.1–3.9 |
298 K (25 °C) |
|
Benzene |
2.3 |
298 K (25 °C) |
|
Dichloromethane |
9.1 |
293 K (20 °C) |
|
Diethyl Ether |
4.3 |
293 K (20 °C) |
|
Dimethylformamide (DMF) |
36.7 |
298 K (25 °C) |
|
Ethanol |
24.3 |
298 K (25 °C) |
|
Ether |
4.3 |
293 K (20 °C) |
|
Fluorinated Refrigerant R-12 |
2 |
298 K (25 °C) |
|
Fluorinated Refrigerant R-22 |
2 |
298 K (25 °C) |
|
Formamide |
109 |
293 K (20 °C) |
|
Liquid Ammonia |
17 |
273 K (0 °C) |
|
Methanol |
32.7 |
298 K (25 °C) |
|
Nitromethane |
35.9 |
303 K (30 °C) |
|
Tetrahydrofuran (THF) |
7.6 |
298 K (25 °C) |
|
Water |
78.4 |
298 K (25 °C) |
Dielectric Constant: Frequently Asked Questions
1. What is the dielectric constant?
The dielectric constant, also known as the relative dielectric constant, measures the ability of a substance to store electrical energy in an electric field. It compares the capability of a material to insulate charges relative to a vacuum.
2. How is the dielectric constant calculated?
It is determined by dividing the capacitance of a capacitor filled with a substance by the capacitance of the same capacitor in a vacuum or in air. Mathematically, it is expressed as ε = C/C₀, where ε is the dielectric constant, C is the capacitance with the substance and C₀ is the capacitance in a vacuum.
3. Are the dielectric constant and breakdown strength the same?
No, they differ. The dielectric constant measures the ability of a material to store electrical energy, whereas the breakdown strength indicates the maximum electric field a material can withstand before electrical breakdown occurs.
4. Why is the dielectric constant important?
The dielectric constant is crucial in various fields. It is used in determining the behaviour of materials in electric fields, in designing capacitors, in understanding solvation effects in chemistry and in analysing material properties in electronics.
5. What affects the dielectric constant?
Factors such as molecular structure, polarity and intermolecular interactions significantly affect the dielectric constant of a substance. Polar substances typically have higher dielectric constants than non-polar substances.
6. Can the dielectric constant vary with temperature and pressure?
Yes, the dielectric constant may change with variations in temperature and pressure. Changes in these parameters can affect molecular interactions and thereby the ability of a substance to store electrical charge.
7. How does the dielectric constant affect solvation?
The dielectric constant influences a solvent's ability to dissolve ionic compounds. Solvents with a high dielectric constant are effective at dissociating ions and stabilising them.
8. What are some practical applications of dielectric constants?
Dielectric constants are applied in various industries. They are used in electronics for capacitor design, in chemistry for solvent selection, in materials science for understanding material properties and in the study of biomolecular interactions.
Reference:
[1] Relative Dielectric Constant. (23/11/2023). In Wikipedia. https://en.wikipedia.org/wiki/Relative_permittivity
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