Hi all,
I'd like to see the performance of NumForce, so I did a harmonic vibrational frequency analysis on NH_3. In the setting, I used default basis set and eht for the guess. I first optimized it with "jobex -level scf -gcart 5", and then did "aoforce" and "NumForce -central -d 0.001889726". The absolute deviations between aoforce and NumFroce are 3.98, 0.59, 2.94, 1.03, 2.24, and 2.29 cm^(-1). From my experience, the error is quite large for such small molecule. After I reviewed all the articles in the topic of "Aoforce and Numforce", I confirmed that the result I got is weird w.r.t. the difference between aoforce and numforce. Do you guys have any idea?
p.s. 0.001889726 equals to 0.001 angstrom which is the default value for most other QM program.
Thank you for your feedback,
Kuan-Yu