Iron complexes of tetradentate macrocyclic ligands containing <i>N</i>-heterocyclic carbene (NHC) donors have been referred to as organometallic heme analogues, but they usually lack the redox noninnocence...

POLYMAT-SILQCOM will be held in Huatulco, Oaxaca, from the 18th to the 23rd of October 2026. We encourage you to participate and present your research results in the different symposia included in the...

Please note that job descriptions are not exhaustive, and you may be asked to take on additional duties that align with the key responsibilities ment...

C2H radicals and CnH polyynes are among the most abundant interstellar polyatomic molecules, predominantly observed in molecular clouds and planetary nebulae. While the C2H– anion is considered a plausible component in the interstellar medium (ISM), it has not yet been detected. Given the extensive study of interstellar polyynes, MCCH/MCCH+ species are also expected to exist in the ISM. Via fundamental metal–carbon bonding, MCCH/MCCH+ molecules exhibit strong polarity, enhancing the intensity of their rotational transitions and improving the chances of astronomical observation. Theoretical spectroscopy enables the generation of molecular reference data to aid in detections. In this study, highly accurate single reference coupled cluster theory [CCSD(T)] is compared to multireference configuration interaction theory (MRCISD+Q) to survey the electronic structure of 3d metal mono acetylide cations (MCCH+, where M = Sc to Zn) which could catalyze gas phase reactions in cold astrochemical environments. CCSD(T) and MRCISD+Q theories gave equivalent predictions of ground electronic states for all cations excluding CoCCH+. The MRCISD+Q ground state for CoCCH+ (4Φ) is multireference and multiconfigurational, and single reference coupled cluster energies could not be converged. The investigated electronic states of MCCH+ arise from interactions between the 1Σ+ ground state of the C2H– anion and the metal dication (M2+). A thorough analysis of multireference character of electronic states is reported. The 3Π excited state of NiCCH+ was the variationally accessible electronic state with the strongest reported multireference character (T1 diagnostic = 0.15, D1 diagnostic = 0.55, C02 = 0.26). Harmonic vibrational frequencies, infrared intensities, and dipole moments are computed for the identified ground states. Theoretical characterization of the ground and excited electronic states of these specific ions will assist in their astronomical detection, constrain laser spectroscopy experiments of the neutral species, and guide characterization in synthetic laboratories.

Solvent-free organosodium is a promising alternative to lithium reagents

ConspectusAlkali metal (AM) cations are often taken for granted as counterions in coordination chemistry and organometallic reactions. However, the AM cation can be more than a bystander in inorganic...

Springer　1968/1/1(月)発売