What does negative anharmonic energy mean in anahrmonic vibrational frequency calculation using Gaussian? And how to resolve those?

I curiously have done some anharmonic vibrational calculations using Gaussian (#p freq=(anharmonic,noraman,savenormalmodes) b3lyp/genecp scf=(maxcyc=1000,tight) scrf=cpcm) and the results puzzled...

05 June 2023 1,870 0 View