Research Articles

Go to each year to access PDF

[78] L. Ferres, L. Evangelisti, A. Maris, S. Melandri, W. Caminati, W. Stahl, H.V.L. Nguyen, Molecules 27, 2730 (2022).

Skeletal torsion tunneling and methyl internal rotation: The coupled large amplitude motions in phenyl acetate

[77] N.N. Dang, H.N. Pham, I. Kleiner, M. Schwell, J.-U. Grabow, H.V.L. Nguyen, Molecules 27, 2639 (2022).

Methyl internal rotation in fruit esters: Chain-length effect observed in the microwave spectrum of methyl hexanoate

[76] L. Kang, H.V.L. Nguyen, C.B. Falls, A.B. Seys, W.C. Pringle, T.A. Blake, S.E. Novick, S.A. Cooke, J. Mol. Spectrosc. 385, 111618 (2022).

The microwave spectrum of the difluorocyanomethyl radical, ĊF2CN

[75] S. Khemissi, M. Schwell, I. Kleiner, H.V.L. Nguyen, Mol. Phys. e2052372 (2022). DOI: 10.1080/00268976.2022.2052372

Influence of π-electron conjugation outside the aromatic ring on the methyl internal rotation of 4-methyl-5-vinylthiazole

[74] J. Demaison, N. Vogt, H.V.L. Nguyen, Chem. Phys. Lett. 794, 139488 (2022).

Determination of rotational constants in the presence of methyl internal rotation: 2-acetylfuran and 2-acetylthiophene as examples

[73] C. Dindić, J. Ludovicy, V. Terzi, A. Lüchow, N. Vogt, J. Demaison, H.V.L. Nguyen, Phys. Chem. Chem. Phys. 24, 3804–3815 (2022).

Determination of the semiexperimental equilibrium structure of 2-acetylthiophene in the presence of methyl internal rotation and substituent effects compared to thiophene

[72] M. Andresen, M. Schwell, H.V.L. Nguyen, J. Mol. Struct. 1247, 131337 (2022).

The two-top molecule 3-penten-2-one: Acetyl methyl torsion in α,β-unsaturated ketones

[71] S. Herbers, O. Zingsheim, H.V.L. Nguyen, L. Bonah, B. Heyne, N. Wehres, S. Schlemmer, J. Chem. Phys. 155, 224302 (2021).

Internal rotation arena: Program performances on the low barrier problem of 4-methylacetophenone

[70] C. Dindić, H.V.L. Nguyen, ChemPhysChem 22, 2420-2428 (2021).

Microwave spectrum of two-top molecule: 2-Acetyl-3-methylthiophene

[69] S. Khemissi, A. Pérez Salvador, H.V.L. Nguyen, J. Phys. Chem. A 125, 8542−8548 (2021).

Large amplitude motions in 2,3-dimethylfluorobenzene: Steric effects failing to interpret hindered methyl torsion

[68] K.P.R. Nair, S. Herbers, J.-U. Grabow, H.V.L. Nguyen, J. Mol. Struct. 1246, 131096 (2021).

Neighborhood matters: Steric effects on methyl internal rotation and chlorine nuclear quadrupole coupling in 2-fluoro-4-chlorotoluene

[67] C. Dindić, A. Lüchow, N. Vogt, J. Demaison, H.V.L. Nguyen, J. Phys. Chem. A 125, 4986−4997 (2021).

Equilibrium structure in the presence of methyl internal rotation: Microwave spectroscopy and quantum chemistry study of the two conformers of 2-acetylfuran

[66] T. Nguyen, W. Stahl, H.V.L. Nguyen, I. Kleiner, J. Chem. Phys. 154, 204304 (2021).

Local versus global approaches to treat two equivalent methyl internal rotations and 14N quadrupole coupling of 2,5-dimethylpyrrole

[65] H.V.L. Nguyen, I. Gulaczyk, M. Kręglewski, I. Kleiner, Coord. Chem. Rev. 436, 213797 (2021).

Large amplitude inversion tunneling motion in ammonia, methylamine, hydrazine, and secondary amines: From structure determination to coordination chemistry

[64] J. Mélan, S. Khemissi, H.V.L. Nguyen, Spectro. Chim. Acta A 253, 119564 (2021).

Steric effects on two inequivalent methyl internal rotations of 3,4-dimethylfluorobenzene

[63] H.V.L. Nguyen, M. Andresen, W. Stahl, Phys. Chem. Chem. Phys. 23, 2930 (2021).

Conformational sampling and large amplitude motion of methyl valerate

[62] K.P.R. Nair, S. Herbers, W.C. Bailey, D.A. Obenchain, A. Lesarri, J.-U. Grabow, H.V.L. Nguyen, Spectro. Chim. Acta A 247, 119120 (2021).

Internal rotation and chlorine nuclear quadrupole coupling in 2-chloro-4-fluorotoluene explored by microwave spectroscopy and quantum chemistry

[61] H.V.L. Nguyen, I. Kleiner, Phys. Sci. Rev. (2021), DOI: 10.1515/psr-2020-0037, online. 

Understanding (coupled) large amplitude motions: The interplay of microwave spectroscopy, spectral modeling, and quantum chemistry

[60] K.J. Koziol, W. Stahl, H.V.L. Nguyen, J. Chem. Phys. 153, 184308 (2020).

The effects of proton tunneling, 14N quadrupole coupling, and methyl internal rotations in the microwave spectrum of ethyl methyl amine

[59] P. Buschmann, K.G. Lengsfeld, K. Aydt, M.K. Jahn, S. Herbers, M.J. Travers, H.V.L. Nguyen, J.-U. Grabow, J. Mol. Spectrosc. 373, 111372 (2020).

Proton inversion tunneling in the rotational spectrum of acetone cyanohydrin

[58] L. Tulimat, H. Mouhib, H.V.L. Nguyen, W. Stahl, J. Mol. Spectrosc. 373, 111356 (2020).

Laboratory rotational spectroscopy of methyl n-propyl sulfide: Conformational analysis and methyl internal rotations

[57] C. Dindic, W. Stahl, H.V.L. Nguyen, Phys. Chem. Chem. Phys. 22, 19704 (2020).

2-Propionylthiophene: Planar, or not planar, that is the question

[56] T. Nguyen, W. Stahl, H.V.L. Nguyen, I. Kleiner, J. Mol. Spectrosc. 372, 111351 (2020).

14N Nuclear quadrupole coupling and methyl internal rotation in 3­-methylpyrrole investigated by microwave spectroscopy

[55] K.P.R. Nair, S. Herbers, H.V.L. Nguyen, J.-U. Grabow, Spectro. Chim. Acta A 242, 118709 (2020).

The structure and low-barrier methyl torsion of 3-fluorotoluene

[54] M. Andresen, D. Schöngen, I. Kleiner, M. Schwell, W. Stahl, H.V.L. Nguyen, ChemPhysChem 21, 2206 (2020).

Internal rotation of the acetyl methyl group in methyl alkyl ketones: The microwave spectrum of octan-2-one

[53] S. Khemissi, H.V.L. Nguyen, ChemPhysChem 21, 1682-1687 (2020).

Two equivalent internal rotations in the microwave spectrum of 2,6-dimethylfluorobenzene

[52] H.V.L. Nguyen, J.-U. Grabow, ChemPhysChem 21, 1243-1248 (2020).

The scent of maibowle – π electron localization in coumarin from its microwave-determined structure

Cover feature

[51] S. Herbers, H.V.L. Nguyen, J. Mol. Spectrosc. 370, 111289 (2020).

Next level achievement of the XIAM code in modeling the microwave spectrum of m-methylanisole

[50] T. Nguyen, V. Van, C. Gutlé, W. Stahl, M. Schwell, I. Kleiner, H.V.L. Nguyen, J. Chem. Phys. 152, 134306 (2020).

The microwave spectrum of 2-methylthiazole: 14N nuclear quadrupole coupling and methyl internal rotation

[49] H.V.L. Nguyen, J. Mol. Struct. 1208, 127909 (2020).

The heavy atom substitution and semi-experimental equilibrium structures of 2-ethylfuran obtained by microwave spectroscopy

[48] R. Hakiri, N. Derbel, W.C. Bailey, H.V.L. Nguyen, H. Mouhib, Mol. Phys. 118, e1728406 (2020).

The heavy atom structures and 33S quadrupole coupling constants of 2-thiophenecarboxaldehyde: insights from microwave spectroscopy

[47] V. Van, T. Nguyen, W. Stahl, H.V.L. Nguyen, I. Kleiner, J. Mol. Struct. 1207, 127787 (2020).

Coupled large amplitude motions: The effects of two methyl internal rotations and 14N quadrupole coupling in 4,5-dimethylthiazole investigated by microwave spectroscopy

[46] S. Herbers, S.M. Fritz, P. Mishra, H.V.L. Nguyen, T.S. Zwier, J. Chem. Phys. 152, 074301 (2020).

Local and global approaches to treat the torsional barriers of 4-methylacetophenone using microwave spectroscopy

[45] M. Andresen, I. Kleiner, M. Schwell, W. Stahl, H.V.L. Nguyen, J. Phys. Chem. A 124, 1353-1361 (2020).

Microwave spectrum and internal rotations of heptan-2-one: A pheromone in the gas phase

[44] V. Van, W. Stahl, M.T. Nguyen, H.V.L. Nguyen, Can. J. Phys. 98, 538-542 (2020).

The smell of coffee: the carbon atom microwave structure of coffee furanone validated by quantum chemistry

[43] T. Nguyen, C. Dindic, W. Stahl, H.V.L. Nguyen, I. Kleiner, Mol. Phys. 118, 1668572 (2020).

14N Nuclear quadrupole coupling and methyl internal rotation in the microwave spectrum of 2-methylpyrrole

[42] L. Ferres, W. Stahl, H.V.L. Nguyen, J. Chem. Phys. 151, 104310 (2019).

Low torsional barrier challenges in the microwave spectrum of 2,4-dimethylanisole

Editor’s pick

[41] M. Andresen, I. Kleiner, M. Schwell, W. Stahl, H.V.L. Nguyen, ChemPhysChem 20, 2063–2073 (2019).

Sensing the molecular structures of hexan-2-one by internal rotation and microwave spectroscopy

Cover feature

[40] L. Ferres, J. Cheung, W. Stahl, H.V.L. Nguyen, J. Phys. Chem. A 123, 3497−3503 (2019).

Conformational effect on the large amplitude motions of 3,4-dimethylanisole explored by microwave spectroscopy

Cover page

[39] K. Eibl, W. Stahl, I. Kleiner, H.V.L. Nguyen, J. Chem. Phys. 149, 144306 (2018).

Conformational effect on the almost free internal rotation in 4-hexyn-3-ol studied by microwave spectroscopy and quantum chemistry

[38] R. Hakiri, N. Derbel, H.V.L. Nguyen, H. Mouhib, Phys. Chem. Chem. Phys. 20, 25577-25582 (2018).

Communication through the furan ring: Conformational effect on the internal rotation of 5-methyl furfural studied by microwave spectroscopy

Cover page

[37] M. Andresen, I. Kleiner, M. Schwell, W. Stahl, H.V.L. Nguyen, J. Phys. Chem. A 122, 7071-7078 (2018).

Acetyl methyl torsion in the microwave spectrum of pentan-2-one

[36] L. Ferres, K.-N. Truong, W. Stahl, H.V.L. Nguyen, ChemPhysChem 19, 1781-1788 (2018).

Interplay between microwave spectroscopy and X-ray diffraction: The molecular structure and large amplitude motions of 2,3-dimethylanisole

[35] L. Ferres, W. Stahl, H.V.L. Nguyen, J. Chem. Phys. 148, 124304 (2018).

Conformational effects on the torsional barriers in m-methylanisole studied by microwave spectroscopy

[34] V. Van, W. Stahl, M. Schwell, H.V.L. Nguyen, J. Mol. Struct. 1156, 348-352 (2018).

Gas-phase conformations of 2-methyl-1,3-dithiolane investigated by microwave spectroscopy

[33] V. Van, J. Bruckhuisen, W. Stahl, V. Ilyushin, H.V.L. Nguyen, J. Mol. Spectrosc. 343, 121-125 (2018).

The torsional barriers of two equivalent methyl internal rotations in 2,5-dimethylfuran investigated by microwave spectroscopy

[32] L. Ferres, W. Stahl, I. Kleiner, H.V.L. Nguyen, J. Mol. Spectrosc. 343, 44-49 (2018).

The effect of internal rotation in p-methyl anisole studied by microwave spectroscopy

[31] L. Ferres, H. Mouhib, W. Stahl, M. Schwell, H.V.L. Nguyen, J. Mol. Spectrosc. 337, 59-64 (2017).

Molecular structure and ring tunneling of phenyl formate as observed by microwave spectroscopy and quantum chemistry

[30] A.O. Hernandez-Castillo, C. Abeysekera, B.M. Hays, I. Kleiner, H.V.L. Nguyen, T.S. Zwier, J. Mol. Spectrosc. 337, 51-58 (2017).

Conformational preferences and internal rotation of methyl butyrate by microwave spectroscopy

[29] L. Ferres, H. Mouhib, W. Stahl, H.V.L. Nguyen, ChemPhysChem 18, 1855-1859 (2017).

Methyl internal rotation in the microwave spectrum of o-methyl anisole

Cover picture

[28] K. Eibl, R. Kannengießer, W. Stahl, H.V.L. Nguyen, I. Kleiner, Mol. Phys. 114, 3483-3489 (2016).

Low barrier methyl rotation in 3-pentyn-1-ol as observed by microwave spectroscopy

[27] L. Sutikdja, W. Stahl, V. Sironneau, H.V.L. Nguyen, I. Kleiner, Chem. Phys. Lett. 663, 145 (2016).

Structure and internal dynamics of n-propyl acetate studied by microwave spectroscopy and quantum chemistry

[26] V. Van, W. Stahl, H.V.L. Nguyen, ChemPhysChem 17, 3223-3228 (2016).

The structure and torsional dynamics of two methyl groups in 2-acetyl-5-methylfuran as observed by microwave Spectroscopy

[25] R. Kannengießer, W. Stahl, H.V.L. Nguyen, J. Phys. Chem. A 120, 5979-5984 (2016).

Two conformers of N,N-diethylpropionamide as observed by microwave spectroscopy and quantum chemistry

[24] R. Kannengießer, W. Stahl, H.V.L. Nguyen, I. Kleiner, J. Phys. Chem. A 120, 3992-3997 (2016).

14N nuclear quadrupole coupling and methyl internal rotation in N-tert-butylacetamide as observed by microwave spectroscopy

[23] A. Jabri, V. Van, H.V.L. Nguyen, W. Stahl, I. Kleiner, ChemPhysChem 17, 2660-2665 (2016).

Probing the methyl torsional barriers of the E and Z isomers of butadienyl acetate by microwave spectroscopy

[22] V. Van, W. Stahl, H.V.L. Nguyen, J. Mol. Struct. 1123, 24 (2016).

The heavy atom microwave structure of 2-methyltetrahydrofuran

[21] L. Ferres, W. Stahl, H.V.L. Nguyen, Mol. Phys. 114, 2788 - 2793 (2016).

The molecular structure of phenetole studied by microwave spectroscopy and quantum chemical calculations

[20] A. Jabri, V. Van, H.V.L. Nguyen, H. Mouhib, F. Kwabia-Tchana, L. Manceron, W. Stahl, I. Kleiner, A&A 589, A127 (2016).

Laboratory microwave, millimeter wave and far-infrared spectra of dimethyl sulfide

[19] V. Van, W. Stahl, H.V.L. Nguyen, Phys. Chem. Chem. Phys. 17, 32111 (2015).

Two equivalent methyl internal rotations in 2,5-dimethylthiophene investigated by microwave spectroscopy

Cover page

[18] R. Kannengießer, W. Stahl, H.V.L. Nguyen, W.C. Bailey, J. Mol. Spectrosc. 317, 50-53 (2015).

14N quadrupole coupling in the microwave spectra of N-vinylformamide

[17] R. Kannengießer, M.J. Lach, W. Stahl, H.V.L. Nguyen, ChemPhysChem 16, 1906-1911 (2015).

Acetyl methyl torsion in N-ethylacetamide: A challenge for microwave spectroscopy and quantum chemistry

[16] Y. Zhao, H.V.L. Nguyen, W. Stahl, J.T. Hougen, J. Mol. Spectrosc. 318, 91 (2015).

Unusual internal rotation coupling in the microwave spectrum of pinacolone

[15] R. Kannengießer, S. Klahm,  H.V.L. Nguyen, A. Lüchow, W. Stahl, J. Chem. Phys. 141, 204308 (2014).

The effects of methyl internal rotation and 14N quadrupole coupling in the microwave spectra of two conformers of N,N-diethylacetamide

[14] H. V. L. Nguyen, A. Jabri, V. Van, W. Stahl, J. Phys. Chem. A 118, 12130 (2014).

Methyl internal rotation in the microwave spectrum of vinyl acetate

[13] V. Van, C. Dindic, H.V.L. Nguyen, W. Stahl, ChemPhysChem 16, 291 (2015).

Conformational transformations of sulfur-containing rings: 2-Methyltetrahydrothiophene gas-phase structures

Cover picture

[12] H.V.L. Nguyen, V. Van, W. Stahl, I. Kleiner, J. Chem. Phys. 140, 214303 (2014).

The effects of two internal rotations in the microwave spectrum of ethyl methyl ketone

[11] H.V.L. Nguyen, I. Kleiner, S.T. Shipman, Y. Mae, K. Hirose, S. Hatanaka, K. Kobayashi, J. Mol. Spectrosc. 299, 17-21 (2014).

Extension of the measurement, assignment, and fit of the rotational spectrum of the two-top molecule methyl acetate

[10] B. Tercero, I. Kleiner, J. Cercicharo, H.V.L. Nguyen, A. López, G.M. Munoz Caro, Astrophys. J. 770, L13 (2013).

Discovery of methyl acetate and gauche ethyl formate in Orion

[9] H.V.L. Nguyen, H. Mouhib, S. Klahm, W. Stahl, I. Kleiner, Phys. Chem. Chem. Phys. 15, 10012 (2013).

A touch of lavender: Gas-phase structure and dynamics of the monoterpene linalool validated by microwave spectroscopy

Cover page

[8] Y. Zhao, W. Stahl, H.V.L. Nguyen, Chem. Phys. Lett. 545, 9-13 (2012).

Ketone physics – structure, conformations, and dynamics of methyl isobutyl ketone explored by microwave spectroscopy and quantum chemical calculations

[7] H.V.L. Nguyen, R. Kannengießer, W. Stahl, Phys. Chem. Chem. Phys. 14, 11753-11758 (2012).

Microwave survey of the conformational landscape exhibited by the propeller molecule triethyl amine

[6] H.V.L. Nguyen, W. Stahl, I. Kleiner, Mol. Phys. 110, 2035-2042 (2012).

Structure and rotational dynamics of methyl propionate studied by microwave spectroscopy

[5] H.V.L. Nguyen and W. Stahl, J. Chem. Phys. 135, 024310 (2011).

The effects of nitrogen inversion tunneling, methyl internal rotation, and 14N quadrupole coupling observed in the rotational spectrum of diethyl amine

[4] H.V.L. Nguyen and W. Stahl, ChemPhysChem 12, 1900-1905 (2011).

The rotational spectrum of diethyl ketone

[3] H.V.L. Nguyen, H. Mouhib, W. Stahl, I. Kleiner, Mol. Phys. 108, 763-770 (2010).

The microwave spectrum of allyl acetate

[2] H.V.L. Nguyen and W. Stahl, J. Mol. Spectrosc. 264, 120-124 (2010).

The microwave spectrum of isopropenyl acetate: An asymmetric molecule with two internal rotors

[1] D. Jelisavac, D.C. Cortés-Gómez, H.V.L. Nguyen, L.W. Sutikdja, W. Stahl, I. Kleiner, J. Mol. Spectrosc. 257, 111-115 (2009).

The microwave spectrum of the trans conformer of ethyl acetate