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Born–Landé Lattice Energy Calculator

🔥 Thermochemistry & Bonding. Use the Born–Landé lattice energy formula to find lattice energy, madelung constant, cation charge |z⁺|, anion charge |z⁻|, ion distance r₀, born exponent n: pick the value you want, type the others, and the answer updates as you go.

E=−NAMz+z−e24πϵ0r0(1−1n)E = -\dfrac{N_A M z^+ z^- e^2}{4\pi\epsilon_0 r_0}\left(1 - \dfrac{1}{n}\right)

Enter the charge sizes (both positive). Default: NaCl, about −755 kJ/mol.

Lattice energy-753.55 kJ/mol

Pick the ○ next to the value you want to find, fill in the others, and it solves as you type.

What each letter means

QuantityUnit
Lattice energykJ/mol
Madelung constantno unit
Cation charge |z⁺|no unit
Anion charge |z⁻|no unit
Ion distance r₀pm
Born exponent nno unit

Worked example

Find the lattice energy when Madelung constant = 1.748, Cation charge |z⁺| = 1, Anion charge |z⁻| = 1, Ion distance r₀ = 282 pm, Born exponent n = 8.

Using E = -(NA M z^+ z^- e²)/(4πε0 r0)(1 - 1/n): Lattice energy = -753.55 kJ/mol.

Frequently asked questions

What is the formula for Born–Landé lattice energy?

E = -(NA M z^+ z^- e²)/(4πε0 r0)(1 - 1/n). Enter the charge sizes (both positive). Default: NaCl, about −755 kJ/mol.

What do the letters stand for, and what units are used?

Lattice energy in kJ/mol, Madelung constant, Cation charge |z⁺|, Anion charge |z⁻|, Ion distance r₀ in pm, Born exponent n.

How do you calculate lattice energy?

Put the values into E = -(NA M z^+ z^- e²)/(4πε0 r0)(1 - 1/n). For example, with Madelung constant = 1.748, Cation charge |z⁺| = 1, Anion charge |z⁻| = 1, Ion distance r₀ = 282 pm, Born exponent n = 8, lattice energy = -753.55 kJ/mol.

Can I solve for a different value?

Yes. In the calculator above, pick the circle next to any value (lattice energy, madelung constant, cation charge |z⁺|, anion charge |z⁻|, ion distance r₀, born exponent n) and fill in the others: it rearranges the formula for you.

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