New computational and experimental studies have been carried out for the MgCCH radical in its X2Σ+ state. Coupled cluster theory with single, double, and perturbative triples, CCSD(T), was used in conjunction with post-CCSD(T) and scalar relativistic additive corrections to compute vibrational quartic force fields for this molecule. From the quartic force fields, higher-order spectroscopic properties, including rotational constants, were obtained. In tandem, the five lowest energy rotational transitions for MgCCH, N = 1→0 through N = 5→4, were measured for the first time using Fourier transform microwave/millimeter wave methods in the frequency range 9 -50 GHz. The radical was created in the Discharge Assisted Laser Ablation Source (DALAS) developed in the Ziurys group. A combined fit of these data with previous millimeter direct absorption measurements have yielded the most accurate rotational constants for MgCCH to date. The computed principle rotational constant lies within 1.51-1.65 MHz of the experimental one, validating the computational approach. High-level theory was then applied to produce accurate rovibrational spectroscopic constants for MgCCH+, including a rotational constant of B0 = 5354.5–5359.5 MHz.. These new predictions will further the experimental study of MgCCH+, and aid in the low-temperature characterization of MgCCH, detected towards the circumstellar shell of IRC+10216, a carbon-rich star. 
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                            Preparation and Characterization of a Formally Ni IV –Oxo Complex with a Triplet Ground State and Application in Oxidation Reactions
                        
                    - Award ID(s):
- 1900380
- PAR ID:
- 10447872
- Date Published:
- Journal Name:
- Journal of the American Chemical Society
- Volume:
- 144
- Issue:
- 49
- ISSN:
- 0002-7863
- Page Range / eLocation ID:
- 22698 to 22712
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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