Complex Refractive Indices of Crystalline Hydrazine from Aerosol Extinction Spectra

Saturn’s tropospheric composition and clouds from Cassini/VIMS 4.6–5.1μm nightside spectroscopy

“…Hydrazine (N 2 H 4 ), from the photolysis of tropospheric NH 3 , is not expected to be a major constituent of the tropospheric clouds, and the single scattering albedo and phase function in Figs. 3 and 4 (Clapp and Miller, 1996) are not sufficiently different in the 4.6-5.1 µm range to distinguish hydrazine from NH 3 ice in the VIMS spectrum. However, one important species is absent from Table 3 that could potentially be a major contributor to IR opacity in this spectral range -diphosphine (P 2 H 4 ), which is expected to be present in significant quantities from PH 3 photolysis.…”

“…between these phase functions, which is mostly governed by the choice of particle sizes (r = 1.0 ± 0.05 µm). Pseudo-NH 4 SH (Nixon et al, 2001) N 2 H 4 (Clapp and Miller, 1996) NH 4 SH (Howett et al, 2007) Grey Isotropic Cloud NH 4 SH (Ferraro et al, 1980) NH 3 (Martonchik et al, 1984) (b) Real Refractive Index 4.5 4.6 4.7 4.8 4.9 5.0 5.1 Wavelength (µm) Pseudo-NH 4 SH (Nixon et al, 2001) N 2 H 4 (Clapp and Miller, 1996) NH 4 SH (Howett et al, 2007) Grey Isotropic Cloud NH 4 SH (Ferraro et al, 1980) NH 3 (Martonchik et al, 1984)…”

Spectroscopy and energetics of the acetylene molecule: dynamical complexity alongside structural simplicity

“…It seems that most (if not, all) of these investigations were prompted by the versatility and anticipated simplicity of C 2 H 2 as a molecule that could usefully probe mechanisms of major interest. For instance, C 2 H 2 was chosen as the molecule for Miller's initial investigation [9] of aerosols formed in low-temperature diffusion cells [9][10][11][12][13][210][211][212][213][214][215][216][217][218]. In introducing their first paper on aerosols, Dunder and Miller [9] viewed C 2 H 2 as 'an appropriate test case .…”

“…Roger also spent a month or so in Sydney with my research group in 1992, by which time I had moved to Macquarie University; this resulted eventually in our only joint paper, on optical double-resonance spectroscopy of the acetylene-argon van der Waals complex [3]. During his time in Sydney, Roger and I had adjacent offices which facilitated frequent enthusiastic discussions of his evolving ideas on intermolecular vibrational energy transfer in photodissociation of van der Waals and H-bonded complexes [4], his emerging interest in observing pendular states to orient such complexes [5] and determine their photofragment distributions [6][7][8], and his plans for further initiatives in spectroscopy of aerosols in low-temperature diffusion cells [9][10][11][12][13]. Our subsequent encounters were occasional and all too few, alas!…”

Investigation of optical laser beam impairment on hypergolic lunarlander exhaust plumes for a lidar feasibility study

“…Assuming a spray of droplets with a Sauter mean diameter of 1 µm [7,8] and a particle density of 0.1 spheres per cubic µm, calculations regarding Mie scattering behavior of the relevant photon wavelengths were carried out using an open source Mie scattering code [9]. Refractive indices n of hydrazine and NTO are wavelength dependent [10]. However, due to lack of reference for n regarding the used laser wavelengths, the refractive indices were estimated and n = 2 applied.…”