I discuss the general scheme and background for Monte Carlo random walks. This is then applied this to the specific case of sampling the “roaming region” of the formaldehyde (H2CO) potential energy surface.

Real-time detection and measurement of subppm levels of formaldehyde in ambient air using diodepumped 3.5 μm difference-frequency generation (DFG) in periodically poled LiNbO3 (PPLN) is reported. Minimum detectable concentration of 30 ppb was achieved with a compact, portable room-temperature gas sensor configured for formaldehyde (H2CO) detection. This sensitivity, coupled with high selectivit...

Detailed semi-empirical interaction potential calculations are performed to determine the potential energy surface experienced by the molecules CO, HCN, H2O and H2CO, when adsorbed on the basal plane (0001) of graphite at low temperature. The potential energy surface is used to find the equilibrium site and configuration of a molecule on the surface and its corresponding adsorption energy. The ...

Abstract. Carbon monoxide (CO), acetylene (C2H2), ethane (C2H6), formaldehyde (H2CO), and hydrogen cyanide (HCN) are important trace gases in the atmosphere. They highly related to biomass burning, fossil fuel combustion, biogenic emissions globally, affecting air quality climate change. However, variations correlations among these species not well known northern China due limited measurements....

A trace gas absorption sensor for formaldehyde (H2CO) detection was developed using a continuous wave, room temperature, low-power consumption interband cascade laser (ICL) at 3.6 μm. The recent availability of ICLs with wavelength ranged between 34 μm enables the sensitive detection of trace gases such as formaldehyde that possesses a strong absorption band in this particular wavelength regio...

We present line observations of different molecular species toward the dense core in L483 and its bipolar outflow powered by the Class 0 object IRAS 181480440. CO(2–1) maps show that the outflow is well collimated and asymmetric, and that its gas is warmer than the surrounding cloud by at least a factor of 2. In contrast with the outflows from other Class 0 objects, the CH3OH(2k–1k) lines in L4...