Question

Which of the following quantities is not changed at different magnetic field strength?

• A. \( \text{Chemical shift (in Hz)} \)
• B. \( \text{Nuclear spin population in an energy state} \)
• C. \( \text{J-coupling constant} \)
• D. \( \text{Energy difference between two energy states of nuclei with nonzero spin quantum number} \)

Hint:

J-coupling constants provide insight into molecular connectivity, regardless of magnetic field strength.

Answer 1

The Correct Option is C

J-coupling constants remain independent of magnetic field strength, representing intramolecular spin-spin interactions. Chemical shift (Hz), nuclear spin populations, and energy differences are influenced by magnetic field variations, altering spectral properties. The J-coupling constant is determined by bond connectivity and electronic environment.