Styryl dyes, specifically LDS group dyes, are known solvatochromic and electrochromic probes for monitoring mitochondrial potential in cellular environments. However, the ability of these dyes to respond to fluctuations in viscosity, pH and temperature has not been established. In this study, we demonstrated that LDS 798 (also known as Styryl-11) can sense environmental viscosity (via fluorescence lifetime changes) as well as pH changes (ratiometric intensity change) in the absence of polarity variations. Polarity changes can be probed by spectral changes using LDS 798. Therefore, all properties of the media should be considered, when these types of dyes are used as electrochormic/solvatochromic sensors in cellular environments.

The linear MgC(3)(-) anion has been identified in the products from the dual Nd:YAG laser ablation of carbon and magnesium rods trapped in solid Ar at ∼12 K. Measurements of (13)C isotopic shifts confirm the identification of the ν(1)(σ) vibrational fundamental at 1797.5 cm(-1). A second fundamental ν(2)(σ) has been tentatively identified at 1190.1 cm(-1). The results are in good agreement with the predictions of density functional theory calculations using the B3LYP functional with the 6-311+G(d) basis set. This is the first optical detection of the linear isomer of MgC(3)(-).

An isomer of ZnC(3) with bent structure in its (1)A(') electronic state has been detected in the products from the dual laser ablation of carbon and zinc rods that were trapped in solid Ar at ~12 K. Measurements of (13)C isotopic shifts have enabled the identification of the ν(1)(a(')) asymmetric carbon stretching fundamental at 1858.9 cm(-1). The experimental results are in good agreement with the predictions of DFT-B3LYP/6-311G(d) calculations that indicate a singlet bent isomer ground state structure with triplet linear and singlet cyclic isomers lying slightly higher in energy. This is the first optical detection of any isomer of ZnC(3).

Linear MnC(3) has been detected in the products from the dual laser ablation of carbon and manganese rods trapped in solid Ar at ∼12 K. The ν(1)(σ) vibrational fundamental, an asymmetric carbon stretching mode, has been identified at 1846.9 cm(-1). Fourier transform infrared measurements of (13)C isotopic shift are in good agreement with the predictions of density functional theory calculations using the mPW1PW91 functional with 6-311+G(3df) basis set. This is the first optical detection of the linear isomer of MnC(3) for which previous photoelectron spectroscopy studies have reported evidence of a cyclic isomer.