Excitation of N2 Molecules as a Density Modifier: A Theoretical Approach


This work presents a theoretical exploration of modifying the volume and density of N2 gas molecules so as to feed gas balloons and zeppelin airships for flying purposes. This research aims to develop a gas system with a lower density than their non-modified ground state gas by studying the properties associated with excited state levels and their differences from the fundamental one. Then, this approach is achieved by altering the micro-molecular or electronic properties of N2 gas to assess the change at the macro-molecular level, such as volume and density. Density functional theory (DFT), time-dependent density functional theory (TD-DFT), and molecular dynamics (MD) computational methods are employed to look for the effects of excited N2 molecules on volume and density at standard conditions. As a result, a density decrease of 2.77% is achieved for the eighth excited state molecule set compared to the ground state system, indicating the feasibility of this approach. Contrasting this system with the traditional hydrogen gas used in zeppelins, N2 gas is a widely available, eco-friendly, and safe source (non-flammable) around Earth, strengthening its suitability as a source for high-tech applications.

Keywords: gas, excited states, DFT, TD-DFT, MD, volume, density modification.


A través de este trabajo se presenta una exploración teórica acerca de la modificación del volumen y densidad del N2 gas con el objetivo de alimentar globos aéreos o aeronaves Zeppelin para propósitos de vuelo. Este estudio apunta hacia el desarrollo de un sistema gaseoso de menor densidad mediante el estudio de propiedades asociadas a niveles excitados de energía, contrastando con el sistema no modificado en estado fundamental. Esta estrategia es conseguida mediante la alteración la las propiedades micro-moleculares o electrónicas del N2 gas para evaluar cambios a nivel macromolecular, tales como el volumen y la densidad. Varios métodos computacionales, tales como la teoría de densidad funcional (DFT), la teoría de densidad funcional dependiente del tiempo (TD-DFT) y dinámica molecular (MD), son empleados para observar los efectos de moléculas excitadas de N2 sobre el volumen y densidad de este gas a condiciones estándar. Como resultado, se consiguió un decremento de la densidad del gas en un 2.77 % para el sistema en octavo estado excitado, comparado con el sistema en estado fundamental; lo cual es indicativo de la factibilidad de esta estrategia. Al contrastar el sistema de estudio con gases tradicionales como el hidrogeno gaseoso usado en zeppelins, el N2 gas es un recurso de amplia disponibilidad alrededor del globo, eco-amigable, y un material seguro (no flamable), lo cual lo hace un recurso ideal para aplicaciones de nuevas tecnologías.

Palabras Clave: N2, gas, estados excitados, DFT, TD-DFT, MD, volumen, modificación de densidad.

[1] McCullough D. The Wright Brothers. Simon & Schuster; 2015; pp. 1532–1536.

[2] Freudenrich C. History of airships and balloons. [Internet]. 2020 [cited 2023 Mar 25]. Available from: https://airship.com.au/history-of-airships-and-balloons/

[3] EARTHDATA NASA. Open Access for Open Sci- ence. Air Mass/density. [Internet]. 2021 [cited 2022 Sep 25]. Available from: https://www.earthdata.nasa.gov/topics/atmosphere/atmospheric-pressure/air-massdensity.

[4] Nukurangi T. Layers of the atmosphere. NIWA. [Internet]. 2021 [cited 2023 Mar 25]. Avail- able from: https://niwa.co.nz/education-and-training/schools/students/layers

[5] Ilie R, Liemohn MW. The outflow of ionospheric Nni- trogen ions: a possible tracer for the altitude de- pendent transport and energization processes of ionospheric plasma. Journal of Geophysical Research: Space Physics. 2016 Sep;121(9):9250– 9255.

[6] Lin MY, Ilie R, Glocer A. The contribution of Nn + ions to earth polar wind. Geophysical Research Letters. 2020 Sep;47(18):4–6.

[7] Mlynczak MG, Hunt LA, Marshall BT. Nitrogen vibrational temperatures in the thermosphere from SABER. Geophysical Research Letters. 2018;45(9):3974–3981.

[8] Campbell L, Brunger MJ, Cartwright DC, Bolorizadeh MA. Role of excited nitrogen in the ionosphere. AIP Conference Proceedings. 2006;876:41–50.

[9] Iriawan H, Andersen SZ, Zhang X, Comer BM, Barrio J, Chen P, et al. Methods for Nitrogen Activation by Re- duction and Oxidation. Nat Rev Methods Primers. 2021;1(1):56–57.

[10] Masero F, Perrin MA, Dey S, Mougel V. Dinitrogen Fixation: Rationalizing Strategies Utilizing Molecular Complexes. Chemistry. 2021 Feb;27(12):3892–3928.

[11] Materials Square. First principles method for excited state dynamics in materials a: time dependent density functional theory (tddft) materials square. [Internet]. [cited 2023 March 25]. Available from: https://www.materialssquare.com/blog/timedependent- dft-en.

[12] Yao Y, Shao Y, Huang J. Density functional theory: A pedagogical overview. WIREs Computattional Molecular Science, 2019; 9(2):6-7, e1395. doi.org/https://doi.org/10.1002/wcms.1395

[13] Olevano V. TDDFT, Excitations, and Spectroscopy. In: Bonitz M, Frauenheim T, Holst B, et al., editors. Struct. Differ. Time Scales. De Gruyter; 2018; pp. 101–142.

[14] Jiang J, Lan Z, Guo W, Chen C. Density functional theory and time dependent density functional theory study of structural, electronic, and spectroscopic properties of natural pigments: betalains. RSC Advances. 2022;12(4):2546–2556.

[15] Srednicki M. Quantum Field Theory. Cambridge Univer- sity Press; 2017.

[16] Rapaport DC. The Art of Molecular Dynamics Simula- tion. 2nd ed. Cambridge University Press; 2018.

[17] Leach AR. Molecular Modelling: Principles and Appli- cations. 2nd ed. Prentice Hall; 2015.

[18] UCAR Center for Science Education. Ultraviolet (UV) Radiation. UCAR Center for Science Education. Ac- cessed Sep 25, 2022. https://scied.ucar.edu/learningzone/ atmosphere/ultraviolet-uv-radiation

[19] Farnik M, Stara I, Cernusak I. Theoretical Study of Electronic Transitions of Molecular Nitro- gen. The Journal of Physical Chemistry A. 2018;122(50):9697–9703.

[20] Neese F, Wennmohs F, Becker U, Riplinger C. The ORCA quantum chemistry program package. The Journal of Physical Chemistry A. 2020 Jun;152(22):224108.

[21] Phillips JC, Braun R, Wang W, Gumbart J, Tajkhor- shid E, Villa E, et al. Scalable molecular dynamics with NAMD. Journal of Computational Chemistry. 2015;36(20):1568–1580.

[22] Clare J. Gillan, Jonathan Tennyson, Brendan M. McLaughlin, and Patrick G. Burke. Low-energy elec- tron impact excitation of the nitrogen molecule: opti- cally forbidden transitions. Journal of Physics B: Atomic, Molecular and Optical Physics. 1996;29(8):L223–L229.

[23] Zheng Q, Chu W, Zhao C, Zhang L, Guo H, Wang Y, et al. Ab initio nonadiabatic molecular dynamics investiga- tions on the excited carriers in condensed matter systems. Wiley Interdisciplinary Reviews: Computational Molecular Science. 2019;9(6):e1411.

[24] Palomares, F. J. Electron impact excitation of nitro- gen molecule: study of optically forbidden transitions. Journal of Physics: Conference Series, 2018; 4-5, 1067(4), 042005. doi.org/https://doi.org/10.1088/1742-6596/1067/4/042005

[25] Snyder HD, Kucukkal TG. Computational chemistry activities with Avogadro and ORCA. Journal of Chemical Education. 2021;98(4):1335–41.

[26] Alhamed YA, Tuckerman ME. Density functional theory investigation of N2 binding and reduction by the FeMo- cofactor of nitrogenase. Journal of Chemical Theory and Computation2016;12(10):4876–4882.

[27] Gruber N, Galloway JN. An Earth-system perspective of the global nitrogen cycle. Nature. 2008 Jan;451(7176):293–296.

[28] Zhang D, Yang W. Dynamic polarizabilities and excitation spectra from a molecular implementation of time dependent density functional response theory: N2 as a case study. The Journal of Chemical Physics. 2016;144(23):234106.

[29] Kukk E, Alanko S, Aksela H. Vibrational excitation of N2 molecules and N2 ions in electron-impact ionization. The Journal of Chemical Physics. 2016;49(12):124001.