Hello candidate,

The relation between force constant in terms of vibrational frequency is given as-

Frequency= 1/2πc ×(√k/reduced Mass), where k refers to the force constant, and c refers to the speed of light. As frequency is given as 425× 10^13 and taking the reduced Mass equal to 14, so the force constant upon Solving- 8.992 × 10^50 kg/sec2.

Have a good day. Hope that it helps you!!