A spline-fitted potential surface for bent triatomic molecules

The rotated-Morse curve cubic spline method developed previously is extended to bent triatomic molecules by using 2D cubic spline. The Yates—Lester potential for bent H₃ is shown to be accurately fitted over the entire range of the three internal coordinates, with a standard deviation of less than 1 kcal mol^?1. The spline method compares favorably in computational speed with the analytical potential.