MODIFIED SUM RULE FOR THE VIBRATIONAL FREQUENCIES OF SYMMETRICAL ISOTOPIC MOLECULES

Journal Article · Fri Mar 15 04:00:00 EST 1963 · Journal of Chemical Physics (U.S.)

DOI:https://doi.org/10.1063/1.1733859· OSTI ID:4700871

Machida, K

BS>A general method of applying the modified sum rule for the vibrational frequencies of symmetrical isotopic molecules was derived. The rule states that the difference in the sum of the frequency parameters between two isotopic molecules A and A/sup */, DELTA sigma = SIGMA gamma (A) - SIGMA gamma (A/sup */, is the same for the appropriate sets I, II,... of the symmetry species. The sets I, II,... are selected in accordance with the interactions between the equivalent atoms involved in the isotopic change from A into A/sup */. Various sum-rule relations are obtained for a given pair of isotopic molecules depending upon the interaction terms of the potential function. The proof of the rule is given by using the property of the transformation from the internal coordinates into the symmetry coordinates. Application of the rule is illustrated for ethylene, benzene, and their deuterated homologs. (auth)

• Research Organization: Kyoto Univ.
• Sponsoring Organization: USDOE
• NSA Number: NSA-17-031113
• OSTI ID: 4700871
• Journal Information: Journal of Chemical Physics (U.S.), Journal Name: Journal of Chemical Physics (U.S.) Vol. Vol: 38; ISSN JCPSA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ATOMS
BENZENE
DEUTERIUM COMPOUNDS
ELECTRIC POTENTIAL
EQUATIONS
ETHYLENE
FREQUENCY
INTERACTIONS
ISOTOPES
MOLECULES
PHYSICS
VIBRATIONS