1. What is NMR Linewidth Activation Energy?

The activation energy (Ea) from NMR linewidth measurements describes the energy barrier for molecular motion that affects the linewidth of NMR signals. For lithium NMR, this typically relates to ionic hopping between sites in solid electrolytes.

2. How Does the Calculator Work?

The calculator uses the Arrhenius equation applied to NMR linewidth:

Where:

• \( \Delta \nu \) — NMR linewidth (Hz)
• \( A \) — Pre-exponential factor
• \( Ea \) — Activation energy (J/mol)
• \( R \) — Gas constant (8.314 J/mol·K)
• \( T \) — Absolute temperature (K)

Explanation: The equation relates the temperature dependence of NMR linewidth to the activation energy of the motional process causing line broadening.

3. Importance of Activation Energy Calculation

Details: Activation energy from NMR linewidth provides insight into ion dynamics in materials, particularly useful for studying solid electrolytes in battery materials.

4. Using the Calculator

Tips: Enter two temperature-linewidth pairs (T₁,Δν₁ and T₂,Δν₂) measured from your NMR experiments. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What temperature range is appropriate?
A: Typically between 150-500K for solid state Li NMR, but depends on your material's behavior.

Q2: How many data points should I use?
A: While this calculator uses two points, for research you should use multiple points to create an Arrhenius plot.

Q3: What affects NMR linewidth?
A: Dipolar interactions, chemical shift anisotropy, and quadrupolar interactions (for I>½ nuclei like ⁷Li).

Q4: What are typical Ea values for Li ion conductors?
A: Typically 0.2-0.6 eV (20-60 kJ/mol) for good Li-ion conductors.

Q5: Can I use this for other nuclei?
A: Yes, the same principles apply to other nuclei, though interpretation may differ based on the dominant relaxation mechanism.