Harmonic Wavenumbers Research Articles

Anharmonicity factors and potential energy constants of B2H6 and B2D6

The anharmonicity factors of B2H6 and B2D6 have been calculated using Dennison’s method. Using the calculated harmonic wave numbers, the valence force constants have been obtained by the Wilson’s F-G matrix method.

Harmonic wave numbers, rotational distortion constants, and thermodynamic properties for partially deuterated and tritiated molecules of the type XYZ2 ( X = N, P, or As; Y, Z = H, D, or T)

Using a harmonic potential energy function, the harmonic wave numbers for partially deuterated and tritiated molecules of the type XYZ 2 ( X = N, P, or As; Y, Z = H, D, or T) have been calculated by the Wilson FG matrix method. The rotational distortion constants for all these molecules also have been calculated on the basis of the first-order perturbation theory of Kivelson and Wilson. Further, with the calculated wave numbers, the molar thermodynamic properties have been obtained for 12 temperatures between 100 and 1000°K for the ideal gaseous state at one atmosphere pressure and for a rigid-rotor, harmonic-oscillator approximation.

Wave numbers, rotational distortion, constants and thermodynamic properties for NT 3, PT 3, and AsT 3

The harmonic wave numbers for NT 3, PT 3, and AsT 3 have been calculated by use of the potential energy constants obtained for the corresponding hydrides and deuterides in a previous investigation by the authors. The anharmonicity factors and therefore the expected spectral frequencies have been evaluated. A first-order perturbation calculation of the rotational distortion constants for the molecules has been made. The molar thermodynamic properties have been obtained from 100 to 1000°K for a rigid-rotor, harmonic-oscillator approximation at 1-atmos pressure.

Propagation of a Finite Number of Waves

IT has been stated as a general proposition by physicists that it is impossible to propagate a finite number of simple harmonic waves without change of type, the reason being that the discontinuity of motion at the beginning and end of the train of waves cannot be represented by a simple sine or cosine function.

I. On an apparatus for facilitating the reduction of tidal observations

The tidal oscillation of the ocean may be represented as the sum of a number of simple harmonic waves which go through their periods approximately once, twice, thrice, four times in a mean solar day. But these simple harmonic waves may be regarded as being rigorously diurnal, semi-diurnal, ter-diurnal, and so forth, if the length of the day referred to be adapted to suit the particular wave under con­sideration.