Experimental investigations of reactions of hot hydrogen atoms with molecular hydrogen and water

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1993

OSTI ID:7014683

Adelman, D E

The state-to-state integral rate constants were measured for the three reactions: (1) D + H[sub 2](vj) [yields] HD(v[prime] = 0,1,2;j) + H at E[sub rel] = 1.4 and 0.8 eV and (2) H + D[sub 2] [yields] HD(v[prime] = 1,j[prime]) + D at E[sub rel] = 2.2 and 2.5 eV, and (3) H + D[sub 2]O [yields] HD(v[prime],j[prime]), + OD at E[sub rel] = 2.7 eV. The reagents were either in the ground state, (v = 0,j), or for the D + H[sub 2] work prepared in the first excited vibrational state, (v = 1, j = 1), by stimulated Raman pumping. Translationally hot D(H) atoms were generated by UV photolysis of D(H)I. Resonance-enhanced multiphoton ionization and time-of-flight mass spectrometry were employed to detect the nascent HD product in a quantum-state-specific manner. For the reaction D + H[sub 2] we find that vibrational excitation of the H[sub 2] reagent results in: (1) substantial HD rotational excitation for each product vibrational state, (2) a [open quotes]heating[close quotes] of the vibrational product state distribution, and (3) almost no change in the total rate into HD(v[prime] = 0,1,2;j[prime]). The experimental results are consistent with a model in which internal energy of the reagents is conserved. Good to excellent agreement is found between the experiment and recent quantum-mechanical (QM) scattering calculations. The reaction H + D[sub 2] [yields] HD(v[prime] = 1,j[prime]) + D was studied at high collision energies. These experiments provide data that will be useful for determining the importance of the Jahn-Teller effect in reactive scattering systems and to the development of theoretical techniques in which the ground and first excited electronic surfaces are included in QM calculations. For the reaction H + D[sub 2]O, approximately 35% (12% in vibration, 23% in rotation) of the available energy is partitioned into the internal modes of the HD product.

• Research Organization: Stanford Univ., CA (United States)
• OSTI ID: 7014683
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201 -- Chemical & Physicochemical Properties
664300* -- Atomic & Molecular Physics-- Collision Phenomena-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
CHEMICAL REACTIONS
DEUTERIDES
DEUTERIUM
DEUTERIUM COMPOUNDS
ELEMENTS
ENERGY LEVELS
EXCITED STATES
HEAVY WATER
HYDROGEN
HYDROGEN COMPOUNDS
HYDROGEN DEUTERIDE
HYDROGEN ISOTOPES
ISOTOPES
LIGHT NUCLEI
NONMETALS
NUCLEI
ODD-ODD NUCLEI
OXYGEN COMPOUNDS
ROTATIONAL STATES
STABLE ISOTOPES
SYNTHESIS
VIBRATIONAL STATES
WATER