Theoretical chemistry & modeling

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grid-container"> <a href="/web/20230929010611/https://www.nist.gov/chemistry">Chemistry</a> </div> <div class="nist-section-header__sub"> <div class="nist-section-header__main grid-container"> <div class="grid-row"> <div class="nist-section-header__title"> <h1 class="nist-page__title">Theoretical chemistry & modeling</h1> </div> </div> </div> </div> </div> </div> <div class="grid-container"> </div> <div class="nist-page__region nist-page__region--main"> <div class="nist-block"> <div class="grid-container margin-y-4"> <div class="paragraph paragraph--type--dynamic-content-list-topic paragraph--view-mode--default"> <div class="nist-region-heading"> <h2> <div class="string">News and Updates</div> </h2> </div> <div class="nist-block "> <div class="viewsreference"><div class="views-element-container"><div class="js-view-dom-id-2cc8661c2377b85b4a936b026ab7296b0bf1bba1a4ee5c917b2b7676c23ecb74"> <div> <article role="article" about="/news-events/news/2019/05/nist-study-identifies-chemical-blends-possible-alternative-refrigerants" typeof="schema:Article" class="nist-teaser"> <div class="nist-teaser__image"> <div class="entity-reference"> <a href="/web/20230929010611/https://www.nist.gov/news-events/news/2019/05/nist-study-identifies-chemical-blends-possible-alternative-refrigerants" hreflang="en"><img loading="lazy" src="/web/20230929010611im_/https://www.nist.gov/sites/default/files/styles/thumbnail/public/images/2019/04/18/18mml026-170403-f-ip756-073-cleaning-hvac-unit-at-nigerien-afb-credit-us-air-force-photo-by-senior-airman-jimmie-d-pike.jpg?itok=V9ewgy_Y" width="71" height="100" alt="A man in brown camouflage clothing, including baseball cap, gloves and ear protection, uses a long pole to clean the inside of an HVAC unit outside a military tent." typeof="foaf:Image"/> </a> </div> </div> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/web/20230929010611/https://www.nist.gov/news-events/news/2019/05/nist-study-identifies-chemical-blends-possible-alternative-refrigerants"><span property="schema:name">NIST Study Identifies Chemical Blends as Possible Alternative Refrigerants</span> </a></h3> <div class="nist-teaser__date"> <div class="daterange"><time datetime="2019-05-29T12:00:00Z">May 29, 2019</time> </div> </div> </header> <div class="nist-teaser__content"> <div property="schema:text" class="text-with-summary"> More than a dozen chemical blends could serve as alternative refrigerants that won’t heat the atmosphere as much as today’s refrigerants do, or catch fire </div> </div> </div> </article> </div> <div> <article role="article" about="/news-events/news/2018/11/nist-simulations-suggest-graphene-can-stretch-be-tunable-ion-filter" typeof="schema:Article" class="nist-teaser"> <div class="nist-teaser__image"> <div class="entity-reference"> <a href="/web/20230929010611/https://www.nist.gov/news-events/news/2018/11/nist-simulations-suggest-graphene-can-stretch-be-tunable-ion-filter" hreflang="en"><img loading="lazy" src="/web/20230929010611im_/https://www.nist.gov/sites/default/files/styles/thumbnail/public/images/2018/11/26/18mml028_graphene-membrane-2mb_crop.jpg?itok=-GntGItB" width="100" height="77" alt="Horizontal blue mesh shaped like chicken wire featuring a regular pattern of some bigger holes. White balls are scattered around and some are going through the big holes." typeof="foaf:Image"/> </a> </div> </div> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/web/20230929010611/https://www.nist.gov/news-events/news/2018/11/nist-simulations-suggest-graphene-can-stretch-be-tunable-ion-filter"><span property="schema:name">NIST Simulations Suggest Graphene Can Stretch to Be a Tunable Ion Filter</span> </a></h3> <div class="nist-teaser__date"> <div class="daterange"><time datetime="2018-11-26T12:00:00Z">November 26, 2018</time> </div> </div> </header> <div class="nist-teaser__content"> <div property="schema:text" class="text-with-summary"> Researchers at the National Institute of Standards and Technology (NIST) have conducted simulations suggesting that graphene, in addition to its many other </div> </div> </div> </article> </div> <div> <article role="article" about="/news-events/news/2018/06/nist-researchers-simulate-simple-logic-nanofluidic-computing" typeof="schema:Article" class="nist-teaser"> <div class="nist-teaser__image"> <div class="entity-reference"> <a href="/web/20230929010611/https://www.nist.gov/news-events/news/2018/06/nist-researchers-simulate-simple-logic-nanofluidic-computing" hreflang="en"><img loading="lazy" src="/web/20230929010611im_/https://www.nist.gov/sites/default/files/styles/thumbnail/public/images/2018/06/26/18mml017_graphene_transistor.png?itok=JIRO_GUU" width="100" height="59" alt="Illustration of gray-colored chains linked together with red holes and purple spheres" typeof="foaf:Image"/> </a> </div> </div> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/web/20230929010611/https://www.nist.gov/news-events/news/2018/06/nist-researchers-simulate-simple-logic-nanofluidic-computing"><span property="schema:name">NIST Researchers Simulate Simple Logic for Nanofluidic Computing</span> </a></h3> <div class="nist-teaser__date"> <div class="daterange"><time datetime="2018-06-29T12:00:00Z">June 29, 2018</time> </div> </div> </header> <div class="nist-teaser__content"> <div property="schema:text" class="text-with-summary"> Invigorating the idea of computers based on fluids instead of silicon, researchers at the National Institute of Standards and Technology (NIST) have shown how </div> </div> </div> </article> </div> <footer> <div class="link-list"><a href="/web/20230929010611/https://www.nist.gov/news-events/news-updates/topic/248441">View All News and Updates</a></div> </footer> </div> </div> </div> </div> </div> </div> <div class="grid-container margin-y-4"> </div> <div class="grid-container margin-y-4"> </div> <div class="grid-container margin-y-4"> <div class="paragraph paragraph--type--dynamic-content-list-topic paragraph--view-mode--default"> <div class="nist-region-heading"> <h2> <div class="string">Projects and Programs</div> </h2> </div> <div class="nist-block "> <div class="viewsreference"><div class="views-element-container"><div class="js-view-dom-id-05748217dd0c5ca9cc4be110eae19d4e536066ad1504d6deb92163e2aa30407a"> <div> <article role="article" about="/programs-projects/ncnr-dac-and-ccus-efforts" class="nist-teaser"> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/web/20230929010611/https://www.nist.gov/programs-projects/ncnr-dac-and-ccus-efforts"><span>NCNR DAC and CCUS efforts</span> </a></h3> <div class="nist-teaser__type"> <div class="nist-badge display-inline-block margin-y-1 nist-badge--blue boolean">Ongoing</div> </div> </header> <div class="nist-teaser__content"> <div class="text-long"> Overview Capture of carbon dioxide from the air (direct air capture; DAC) combined with energy efficiency and carbon capture, utilization and storage (CCUS) </div> </div> </div> </article> </div> <div> <article role="article" about="/programs-projects/measuring-intermolecular-interactions-electro-acoustic-spectroscopy" class="nist-teaser"> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/web/20230929010611/https://www.nist.gov/programs-projects/measuring-intermolecular-interactions-electro-acoustic-spectroscopy"><span>Measuring Intermolecular Interactions with Electro-Acoustic Spectroscopy</span> </a></h3> <div class="nist-teaser__type"> <div class="nist-badge display-inline-block margin-y-1 nist-badge--blue boolean">Ongoing</div> </div> </header> <div class="nist-teaser__content"> <div class="text-long"> NIST’s Material Measurement Laboratory and Communications Technology Laboratory are developing a new spectroscopy for intermolecular interactions. The team is </div> </div> </div> </article> </div> <div> <article role="article" about="/programs-projects/macromolecular-architectures" class="nist-teaser"> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/web/20230929010611/https://www.nist.gov/programs-projects/macromolecular-architectures"><span>Macromolecular Architectures</span> </a></h3> <div class="nist-teaser__type"> <div class="nist-badge display-inline-block margin-y-1 nist-badge--blue boolean">Ongoing</div> </div> </header> <div class="nist-teaser__content"> <div class="text-long"> There is always a degree of uncertainty surrounding measurements of polymeric materials, especially complex mixtures with varying distributions in chemistry </div> </div> </div> </article> </div> <div> <article role="article" about="/programs-projects/far-infrared-spectroscopy-biomolecules-archived" class="nist-teaser"> <div class="nist-teaser__image"> <div class="entity-reference"> <a href="/web/20230929010611/https://www.nist.gov/programs-projects/far-infrared-spectroscopy-biomolecules-archived" hreflang="en"><img loading="lazy" src="/web/20230929010611im_/https://www.nist.gov/sites/default/files/styles/thumbnail/public/images/2017/02/03/tripeptides.gif?itok=odS4Tug-" width="90" height="100" alt="tripeptides" typeof="foaf:Image"/> </a> </div> </div> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/web/20230929010611/https://www.nist.gov/programs-projects/far-infrared-spectroscopy-biomolecules-archived"><span>Far-infrared Spectroscopy of Biomolecules (Archived)</span> </a></h3> <div class="nist-teaser__type"> <div class="nist-badge display-inline-block margin-y-1 nist-badge--green boolean">Completed</div> </div> </header> <div class="nist-teaser__content"> <div class="text-long"> Far-infrared (or terahertz/THz, ca. 25 to 300 micron wavelength) femtosecond pulsed laser and Fourier-transform infrared methods are employed to measure </div> </div> </div> </article> </div> <footer> <div class="link-list"><a href="/web/20230929010611/https://www.nist.gov/laboratories/projects-programs/topic/248441">View All Projects/Programs</a></div> </footer> </div> </div> </div> </div> </div> </div> <div class="grid-container margin-y-4"> <div class="paragraph paragraph--type--dynamic-content-list-topic paragraph--view-mode--default"> <div class="nist-region-heading"> <h2> <div class="string">Publications</div> </h2> </div> <div class="nist-block "> <div class="viewsreference"><div class="views-element-container"><div class="js-view-dom-id-05a94cf978351e4ccf8d07fd6bb988f2f58131735bd382cecbc734346a0fddcb"> <div> <article role="article" about="/publications/divalent-ions-mediators-carbonylation-cardiac-myosin-binding-protein-c" class="nist-teaser"> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/web/20230929010611/https://www.nist.gov/publications/divalent-ions-mediators-carbonylation-cardiac-myosin-binding-protein-c"><span>Divalent ions as mediators of carbonylation in cardiac myosin binding protein C</span> </a></h3> <div class="nist-teaser__date"> <div class="daterange"><time datetime="2023-11-01T12:00:00Z">November 1, 2023</time> </div> </div> <div class="nist-teaser__type"> <div class="nist-field nist-field--label-inline text-long"> <div class="nist-field__label">Author(s)</div> <div class="nist-field__item"><span class="nist-author">Christina Bergonzo</span>, Baikuntha Aryal, Ashutosh Rao</div> </div> </div> </header> <div class="nist-teaser__content"> <div class="text-with-summary"> The dosing and efficacy of chemotherapeutic drugs can be limited by toxicity caused by off-pathway reactions. One hypothesis for how such toxicity arises is via </div> </div> </div> </article> </div> <div> <article role="article" about="/publications/prediction-sustainable-aviation-fuel-properties-liquid-hydrocarbons-hydrotreating" class="nist-teaser"> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/web/20230929010611/https://www.nist.gov/publications/prediction-sustainable-aviation-fuel-properties-liquid-hydrocarbons-hydrotreating"><span>Prediction of Sustainable Aviation Fuel Properties for Liquid Hydrocarbons from Hydrotreating Biomass Catalytic Fast Pyrolysis Derived Organic Intermediates</span> </a></h3> <div class="nist-teaser__date"> <div class="daterange"><time datetime="2023-04-11T12:00:00Z">April 11, 2023</time> </div> </div> <div class="nist-teaser__type"> <div class="nist-field nist-field--label-inline text-long"> <div class="nist-field__label">Author(s)</div> <div class="nist-field__item">Suphat Watanasiri, Kristiina Iisa, <span class="nist-author">Eugene Paulechka</span>, Earl Christensen, <span class="nist-author">Chris Muzny</span>, Abhijit Dutta</div> </div> </div> </header> <div class="nist-teaser__content"> <div class="text-with-summary"> Catalytic fast pyrolysis (CFP) of wood, woody residues, and agricultural waste has the potential to produce organic liquid intermediates that can be </div> </div> </div> </article> </div> <div> <article role="article" about="/publications/simulating-influence-supporting-electrolyte-concentration-copper-electrodeposition" class="nist-teaser"> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/web/20230929010611/https://www.nist.gov/publications/simulating-influence-supporting-electrolyte-concentration-copper-electrodeposition"><span>Simulating the Influence of Supporting Electrolyte Concentration on Copper Electrodeposition in Microvias</span> </a></h3> <div class="nist-teaser__date"> <div class="daterange"><time datetime="2023-01-18T12:00:00Z">January 18, 2023</time> </div> </div> <div class="nist-teaser__type"> <div class="nist-field nist-field--label-inline text-long"> <div class="nist-field__label">Author(s)</div> <div class="nist-field__item"><span class="nist-author">Trevor Braun</span>, Jimmy John, Nagarajan Jayaraju, <span class="nist-author">Daniel Josell</span>, <span class="nist-author">Thomas P. Moffat</span></div> </div> </div> </header> <div class="nist-teaser__content"> <div class="text-with-summary"> Robust, void-free Cu electrodeposition in high-aspect ratio features relies on careful tuning of electrolyte additives and electrochemical parameters for a </div> </div> </div> </article> </div> <div> <article role="article" about="/publications/conformational-dynamics-hepatitis-b-virus-pre-genomic-rna-multiple-time-scales" class="nist-teaser"> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/web/20230929010611/https://www.nist.gov/publications/conformational-dynamics-hepatitis-b-virus-pre-genomic-rna-multiple-time-scales"><span>Conformational dynamics of the hepatitis B virus pre-genomic RNA on multiple time scales: implications for viral replication</span> </a></h3> <div class="nist-teaser__date"> <div class="daterange"><time datetime="2022-09-30T12:00:00Z">September 30, 2022</time> </div> </div> <div class="nist-teaser__type"> <div class="nist-field nist-field--label-inline text-long"> <div class="nist-field__label">Author(s)</div> <div class="nist-field__item">Lucasz T. Olenginski, Wojciech K. Kasprzak, <span class="nist-author">Christina Bergonzo</span>, Bruce A. Shapiro, Theodore Kwaku Dayie</div> </div> </div> </header> <div class="nist-teaser__content"> <div class="text-with-summary"> HBV replication is initiated by the binding of polymerase (P) to epsilon (ε), a 61 nucleotide (nt) cis -acting regulatory stem-loop RNA located at the 5′-end of </div> </div> </div> </article> </div> </div> </div> </div> </div> </div> </div> <div class="grid-container margin-y-4"> </div> <div class="grid-container margin-y-4"> </div> <div class="grid-container margin-y-4"> </div> <div class="grid-container margin-y-4"> </div> </div> </div> </section> </div> <div data-elastic-exclude>  <footer class="nist-footer padding-bottom-4"> <div class="grid-container nist-footer__info"> <div class="grid-row"> <div class="tablet:grid-col-6"> <div class="nist-footer__logo"> <a href="/web/20230929010611/https://www.nist.gov/" title="National Institute of Standards and Technology" rel="home"> <img class="nist-footer__logo-img" src="/web/20230929010611im_/https://www.nist.gov/libraries/nist-component-library/dist/img/logo/NIST-Logo-Brand-White.svg" alt="National Institute of Standards and Technology logo" width="300px" height="42px"/> </a> </div> <div class="nist-footer__contact"> <h3 class="nist-footer__contact-heading">HEADQUARTERS</h3> <address> 100 Bureau Drive<br> Gaithersburg, MD 20899<br> <a href="https://web.archive.org/web/20230929010611/tel:301-975-2000">301-975-2000</a> </address> <p> <a href="https://web.archive.org/web/20230929010611/mailto:do-webmaster@nist.gov">Webmaster</a> | <a href="https://web.archive.org/web/20230929010611/https://www.nist.gov/about-nist/contact-us">Contact Us</a> | <a href="https://web.archive.org/web/20230929010611/https://www.nist.gov/visit">Our Other Offices</a> </p> </div> </div> <div class="tablet:grid-col-6"> <div class="nist-footer__social-links"> <a class="nist-social nist-social--twitter-white" href="https://web.archive.org/web/20230929010611/https://twitter.com/NIST"> <span>Twitter</span> </a> <a class="nist-social nist-social--facebook-white" href="https://web.archive.org/web/20230929010611/https://www.facebook.com/NIST"> <span>Facebook</span> </a> <a class="nist-social nist-social--linkedin-white" href="https://web.archive.org/web/20230929010611/https://www.linkedin.com/company/nist"> <span>LinkedIn</span> </a> <a class="nist-social nist-social--instagram-white" href="https://web.archive.org/web/20230929010611/https://www.instagram.com/nist/"> <span>Instagram</span> </a> <a class="nist-social nist-social--youtube-white" href="https://web.archive.org/web/20230929010611/https://www.youtube.com/NIST"> <span>YouTube</span> </a> <a class="nist-social nist-social--giphy-white" href="https://web.archive.org/web/20230929010611/https://giphy.com/nist"> <span>Giphy</span> </a> <a class="nist-social nist-social--rss-white" href="https://web.archive.org/web/20230929010611/https://www.nist.gov/news-events/nist-rss-feeds"> <span>RSS Feed</span> </a> <a class="nist-social nist-social--envelope-white" href="https://web.archive.org/web/20230929010611/https://public.govdelivery.com/accounts/USNIST/subscriber/new"> <span>Mailing List</span> </a> </div> <div class="nist-footer__feedback"> How are we doing? 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