{"id":2,"date":"2022-11-17T15:04:57","date_gmt":"2022-11-17T15:04:57","guid":{"rendered":"https:\/\/sites.tntech.edu\/grulab\/?page_id=2"},"modified":"2025-05-21T10:16:55","modified_gmt":"2025-05-21T15:16:55","slug":"sample-page","status":"publish","type":"page","link":"https:\/\/sites.tntech.edu\/grulab\/","title":{"rendered":"Welcome to the Gru Lab at Tennessee Tech!"},"content":{"rendered":"\n

Welcome to the Gru Lab at Tennessee Tech University!<\/h4>\n\n\n\n

The Gurusinghe Research Lab at Tennessee Tech University, \u201cGru Lab\u201d, studies molecular spectroscopy and reaction dynamics\/kinetics using various Fourier transform microwave and millimeterwave (FTMW and FTmmW) spectroscopic and resonance-enhanced ionization techniques.<\/p>\n\n\n\n

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The Instrument: L-Shaped Fourier transform microwave (L-FTMW) spectrometer <\/h4>\n\n\n\n

Our lab’s newest custom-built rotational spectrometer features a novel L-shaped configuration<\/strong> that uniquely combines cavity-enhanced and chirped-pulse Fourier-transform microwave (FTMW) spectroscopy in a single instrument. This innovative geometry offers a low-cost and straightforward design for integrating these two complementary techniques, while also simplifying integration with external photolysis lasers.<\/p>\n\n\n\n

The cavity-enhanced microwave setup<\/strong> employs a Fabry\u2013Perot resonator to boost sensitivity and achieve high spectral resolution (~ 2.5 kHz) making it ideal for resolving subtle hyperfine splittings and extracting detailed molecular information. In parallel, the chirped-pulse microwave setup<\/strong> provides rapid, broadband spectral coverage, enabling efficient surveys of complex mixtures and time-dependent tracking of multiple species simultaneously. The chirped-pulse system\u2019s broadband horn antennas are mounted externally on a microwave-transparent polycarbonate chamber, allowing flexible repositioning along the molecular beam path. A multi-antenna mount also allows seamless switching between different frequency bands, greatly improving efficiency in broadband data collection.<\/p>\n\n\n\n

Together, this integrated dual-technique platform opens new possibilities for addressing fundamental chemical questions and probing astrochemically relevant molecules with both precision and speed.<\/p>\n\n\n\n

<\/p>\n\n\n\n

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Our latest research: Near-free rotor limit quantum tunnelling in 3-methylstyrene conformations<\/h4>\n\n\n\n

Our latest study presents the first high-resolution rotational spectra of both cis and trans conformers of 3-methylstyrene, a molecule exhibiting near free-rotor methyl torsion. Using jet-cooled FTMW spectroscopy, we precisely measured quantum tunneling splittings arising from extremely low torsional barriers. These splittings were rigorously analyzed and fitted using multiple torsion-rotation Hamiltonians (XIAM and BELGI-Cs), enabling detailed characterization of methyl internal rotation and conformer-dependent dynamics.<\/p>\n\n\n\n

Beyond torsional analysis, the work makes a valuable contribution to the long-debated question of structural planarity in styrene derivatives. By deriving second moments from experimentally determined rotational constants, we provided strong evidence for planar heavy-atom geometries in both conformers, despite minimal energy differences and competing steric effects.<\/p>\n\n\n\n

This research was featured in the Journal of Chemical Physics Emerging Investigators Special Collection and selected for the cover of the January 2025 issue.<\/p>\n\n\n\n

<\/p>\n\n\n\n

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Welcome to the Gru Lab at Tennessee Tech University! The Gurusinghe Research Lab at Tennessee Tech University, \u201cGru Lab\u201d, studies molecular spectroscopy and reaction dynamics\/kinetics using various Fourier transform microwave and millimeterwave (FTMW and FTmmW) spectroscopic and resonance-enhanced ionization techniques. The Instrument: L-Shaped Fourier transform microwave (L-FTMW) spectrometer Our lab’s newest custom-built rotational spectrometer features […]<\/p>\n","protected":false},"author":167,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"open","template":"custom-page.php","meta":{"footnotes":""},"class_list":["post-2","page","type-page","status-publish","czr-hentry"],"_links":{"self":[{"href":"https:\/\/sites.tntech.edu\/grulab\/wp-json\/wp\/v2\/pages\/2","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sites.tntech.edu\/grulab\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/sites.tntech.edu\/grulab\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/sites.tntech.edu\/grulab\/wp-json\/wp\/v2\/users\/167"}],"replies":[{"embeddable":true,"href":"https:\/\/sites.tntech.edu\/grulab\/wp-json\/wp\/v2\/comments?post=2"}],"version-history":[{"count":41,"href":"https:\/\/sites.tntech.edu\/grulab\/wp-json\/wp\/v2\/pages\/2\/revisions"}],"predecessor-version":[{"id":980,"href":"https:\/\/sites.tntech.edu\/grulab\/wp-json\/wp\/v2\/pages\/2\/revisions\/980"}],"wp:attachment":[{"href":"https:\/\/sites.tntech.edu\/grulab\/wp-json\/wp\/v2\/media?parent=2"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}