Formation of electronically excited Mn sub x O from the oxidation of small manganese clusters

Journal Article · Thu Jun 15 00:00:00 EDT 1989 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100349a048· OSTI ID:6788451

Devore, T C; Woodward, J R; Gole, J L ^[1]

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1. Georgia Institute of Technology, Atlanta (USA)

The chemiluminescent reactions of manganese atoms and clusters with ozone have been studied under multiple-collision conditions. Manganese atoms entrained in room-temperature argon or helium react with ozone to form the lowest lying MnO* A{sup 6}{Sigma}{sup +} excited electron state (Mn to O{sub 3} + Ar (He) {yields} MnO*(A{sup 6}{Sigma}{sup +}) + O{sub 2} + Ar (He)), producing a strong chemiluminescent signal corresponding to the MnO A{sup 6}{Sigma}{sup +}-X{sup 6}{Sigma}{sup +} band system. A high flux of manganese vapor is entrained in liquid N{sub 2} cooled argon to induce clustering. This entrained mixture subsequently reacts with ozone to produce a new complex emission system (accompanies MnO A-X system) containing at least 72 bands and extending from 720 to 970 nm. The new system, which is not present when the carrier gas is not cooled, increases precipitously with entrainment gas cooling and increased metal flux. The observed ands are fit within experimental error by the expression {nu}{sub {nu}1},{nu}1{double prime},{nu}{sub 3{prime}},{nu}{sub 3{double prime}} = 12512 + 600{nu}{sub 1}{prime} -534{nu}{sub 1}{double prime} + 360{nu}{sub 3}{prime} -306{nu}{sub 3}{double prime}, where all values are in cm{sup {minus}1}. The ground-state spacing of 306 cm{sup {minus}1} is assigned as an Mn-Mn stretch. The 534-cm{sup {minus}1} spacing is assigned to an MnO stretch, and the emitting molecule is believed to be the asymmetrical Mn-Mn-O isomer. The Mn-Mn stretch frequency is in excellent agreement with a frequency estimated for Mn{sub 2}{sup +} by averaging the derived force constants for Mn{sub 2} and Cr{sub 2}. The MnO stretching frequency is considerably lower than the 840-cm{sup {minus}1} diatomic frequency, lying intermediate to those of KO (384 cm{sup {minus}1}) and CaO (733 cm{sup {minus}1}).

• OSTI ID: 6788451
• Journal Information: Journal of Physical Chemistry; (USA), Vol. 93:12; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
MANGANESE OXIDES
EXCITED STATES
CHEMILUMINESCENCE
CLUSTER MODEL
DATA ANALYSIS
EXPERIMENTAL DATA
MEASURING INSTRUMENTS
MEASURING METHODS
MEDIUM TEMPERATURE
CHALCOGENIDES
DATA
ENERGY LEVELS
INFORMATION
LUMINESCENCE
MANGANESE COMPOUNDS
MATHEMATICAL MODELS
NUCLEAR MODELS
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
360100* - Metals & Alloys
360102 - Metals & Alloys- Structure & Phase Studies
360104 - Metals & Alloys- Physical Properties
400201 - Chemical & Physicochemical Properties