Implementations in CP2k

CP2k is a very powerful program package for performing electron structure calculations of periodic bulk phase systems.

https://www.cp2k.org

During my scientific guest visit at the University of Zurich in the group of Prof. Jürg Hutter, I have implemented several new features into CP2k:

The Voronoi integration, which we have developed in 2015, is a technique to compute molecular electromagnetic properties such as the electric dipole moment and the electric quadrupole tensor via integration of the total electron density within Voronoi cells. These properties, in turn, are required for computing vibrational spectra from AIMD simulations. I have implemented the Voronoi integration into CP2k, it is available since release 8.1 (December 2020).
See the &DFT/&PRINT/&VORONOI manual section.

In 2018, we have developed a lossless compression algorithm for volumetric data trajectories, and a corresponding new file format, which is the bqb format. I have implemented support for writing the total electron density in bqb format into CP2k, it is available since release 8.1 (December 2020).
See the &DFT/&PRINT/&E_DENSITY_BQB manual section.

Note: If you compile CP2k 8.1 or newer via the Toolchain script, these features will automatically be included by default, and the library will automatically be downloaded and compiled in the process. If you prefer not to use the Toolchain, you need to download and compile the libvori source code from here.

— Related Publications —

32 of my publications are based on CP2k calculations:

The numbers in front of the articles below refer to the full chronological publication list.

64	M. Iannuzzi, J. Wilhelm, F. Stein, A. Bussy, H. Elgabarty, D. Golze, A.-S. Hehn, M. Graml, Š. Marek, B. Sertcan Gökmen, C. Schran, H. Forbert, R. Khaliullin, A. Kozhevnikov, M. Taillefumier, R. Meli, V. Rybkin, M. Brehm, R. Schade, O. Schütt, J. Pototschnig, H. Mirhosseini, A. Knüpfer, D. Marx, M. Krack, J. Hutter, T. Kühne: "The CP2K Program Package Made Simple" J. Phys. Chem. B 2026, accepted*. (DOI `10.1021/acs.jpcb.5c05851` ) ⭳Bib
63	E. Mangiacapre, Z. Barhoumi, M. Brehm, F. Castiglione, V. Di Lisio, A. Triolo, O. Russina: "Choline Acetate/Water Mixtures: Physicochemical Properties and Structural Organization" Molecules 2025, 30 (16), 3403. (DOI `10.3390/molecules30163403` ) ⭳Bib
62	Z. Zhao, C. Weinberger, J. Steube, M. Bauer, M. Brehm, M. Tiemann: "Fast-Responding O2 Gas Sensor Based on Luminescent Europium Metal-Organic Frameworks (MOF-76)" Adv. Funct. Mater. 2025, accepted*, e11190. (1 citations, DOI `10.1002/adfm.202511190` ) ⭳Bib
60	E. Roos, C. Gradaus, D. Sebastiani, M. Brehm: "A Force Field for the Solubility of Cellulose in DMSO/Ionic Liquids" Cellulose 2024*, 31, 4793–4815. (7 citations, DOI `10.1007/s10570-024-05854-4` ) ⭳Bib
58	E. Roos, D. Sebastiani, M. Brehm: "BILFF: All-Atom Force Field for Modeling Triazolium- and Benzoate-Based Ionic Liquids" Molecules 2023, 28 (22)*, 7592. (3 citations, DOI `10.3390/molecules28227592` ) ⭳Bib
56	E. Roos, D. Sebastiani, M. Brehm: "A Force Field for Bio-Polymers in Ionic Liquids (BILFF) – Part 2: Cellulose in [EMIm][OAc] / Water Mixtures" Phys. Chem. Chem. Phys. 2023, 25 (12)*, 8755–8766. (4 citations, DOI `10.1039/D2CP05636D` ) ⭳Bib
54	R. Chahal, S. Roy, M. Brehm, S. Banerjee, V. Bryantsev, S. Lam: "Transferable Deep Learning Potential Reveals Intermediate-Range Ordering Effects in LiF–NaF–ZrF₄ Molten Salt" JACS Au 2022, 2 (12), 2693–2702. (40 citations, DOI `10.1021/jacsau.2c00526` ) ⭳Bib
53	T. Frömbgen, J. Blasius, V. Alizadeh, A. Chaumont, M. Brehm, B. Kirchner: "Cluster Analysis in Liquids: A Novel Tool in TRAVIS" J. Chem. Inf. Model. 2022, 62 (22), 5634–5644. (25 citations, DOI `10.1021/acs.jcim.2c01244` ) ⭳Bib
51	Y. Yang, J. Cheramy, M. Brehm, Y. Xu: "Raman Optical Activity of N-Acetyl-L-Cysteine in Water and in Methanol: The “Clusters-in-a-Liquid” Model and ab initio Molecular Dynamics Simulations" ChemPhysChem 2022, 23 (11), e202200161. (14 citations, DOI `10.1002/cphc.202200161` ) ⭳Bib
49	S. Roy, M. Brehm, S. Sharma, F. Wu, D. Maltsev, P. Halstenberg, L. Gallington, S. Mahurin, S. Dai, A. Ivanov, C. Margulis, V. Bryantsev: "Unraveling Local Structure of Molten Salts via X-Ray Scattering, Raman Spectroscopy, and ab initio Molecular Dynamics" J. Phys. Chem. B 2021, 125 (22), 5971–5982. (48 citations*, DOI `10.1021/acs.jpcb.1c03786` ) ⭳Bib
48	M. Brehm, M. Thomas: "Optimized Atomic Partial Charges and Radii Defined by Radical Voronoi Tessellation of Bulk Phase Simulations" Molecules 2021, 26 (7)*, 1875. (9 citations, DOI `10.3390/molecules26071875` ) ⭳Bib
45	E. Roos, M. Brehm: "A Force Field for Bio-Polymers in Ionic Liquids (BILFF) – Part 1: [EMIm][OAc] / Water Mixtures" Phys. Chem. Chem. Phys. 2021*, 23, 1242–1253. (12 citations, DOI `10.1039/D0CP04537C` ) ⭳Bib
43	M. Weiß, M. Brehm: "Exploring Free Energy Profiles of Enantioselective Organocatalytic Aldol Reactions under Full Solvent Influence" Molecules 2020, 25 (24)*, 5861. (7 citations, DOI `10.3390/molecules25245861` ) ⭳Bib
37	L. Scarbath-Evers, R. Hammer, D. Golze, M. Brehm, D. Sebastiani, W. Widdra: "From Flat to Tilted: Gradual Interfaces in Organic Thin Film Growth" Nanoscale 2020*, 12, 3834–3845. (5 citations, DOI `10.1039/C9NR06592J` ) ⭳Bib
36	M. Brehm, M. Thomas: "Computing Bulk Phase Resonance Raman Spectra from ab initio Molecular Dynamics and Real-Time TDDFT" J. Chem. Theory Comput. 2019, 15 (7)*, 3901–3905. (19 citations, DOI `10.1021/acs.jctc.9b00512` ) ⭳Bib
31	M. Brehm, D. Sebastiani: "Simulating Structure and Dynamics in Small Droplets of 1-Ethyl-3-Methylimidazolium Acetate" J. Chem. Phys. 2018, 148, 193802. (23 citations*, DOI `10.1063/1.5010342` ) ⭳Bib
26	M. Brehm, M. Thomas: "Computing Bulk Phase Raman Optical Activity Spectra from ab initio Molecular Dynamics Simulations" J. Phys. Chem. Lett. 2017, 8 (14), 3409–3414. (31 citations*, DOI `10.1021/acs.jpclett.7b01616` ) ⭳Bib
23	M. Thomas, M. Brehm, B. Kirchner: "Voronoi Dipole Moments for the Simulation of Bulk Phase Vibrational Spectra" Phys. Chem. Chem. Phys. 2015, 17, 3207–3213. (107 citations, DOI `10.1039/C4CP05272B` ) ⭳Bib
20	A. Stark, M. Brehm, M. Brüssel, S. B. C. Lehmann, A. S. Pensado, M. Schöppke, B. Kirchner: "A Theoretical and Experimental Chemist’s Joint View on Hydrogen Bonding in Ionic Liquids and Their Binary Mixtures" Top. Curr. Chem. 2014, 351, 149–187. (39 citations*, DOI `10.1007/128_2013_485` ) ⭳Bib
19	M. Thomas, M. Brehm, O. Hollóczki, Z. Kelemen, L. Nyulászi, T. Pasinszki, B. Kirchner: "Simulating the Vibrational Spectra of Ionic Liquid Systems: 1-Ethyl-3-Methylimidazolium Acetate and its Mixtures" J. Chem. Phys. 2014, 141, 024510. (87 citations, DOI `10.1063/1.4887082` ) ⭳Bib
17	S. Zahn, M. Brehm, M. Brüssel, O. Hollóczki, M. Kohagen, S. B. C. Lehmann, F. Malberg, A. S. Pensado, M. Schöppke, H. Weber, B. Kirchner: "Understanding Ionic Liquids from Theoretical Methods" J. Mol. Liq. 2014, 192, 71–76. (64 citations*, DOI `10.1016/j.molliq.2013.08.015` ) ⭳Bib
16	M. Thomas, M. Brehm, O. Hollóczki, B. Kirchner: "How Can a Carbene be Active in an Ionic Liquid?" Chem. Eur. J 2014, 20 (6), 1622–1629. (49 citations, DOI `10.1002/chem.201303329` ) ⭳Bib
15	F. Malberg, M. Brehm, O. Hollóczki, A. S. Pensado, B. Kirchner: "Understanding the Evaporation of Ionic Liquids using the Example of 1-Ethyl-3-Methylimidazolium Ethylsulfate" Phys. Chem. Chem. Phys. 2013, 15, 18424–18436. (31 citations*, DOI `10.1039/C3CP52966E` ) ⭳Bib
14	M. Thomas, M. Brehm, R. Fligg, P. Vöhringer, B. Kirchner: "Computing Vibrational Spectra from ab initio Molecular Dynamics" Phys. Chem. Chem. Phys. 2013, 15, 6608–6622. (491 citations*, DOI `10.1039/C3CP44302G` ) ⭳Bib
13	M. Brehm, H. Weber, A. S. Pensado, A. Stark, B. Kirchner: "Liquid Structure and Cluster Formation in Ionic Liquid/Water Mixtures – An Extensive ab initio Molecular Dynamics Study on 1-Ethyl-3-Methylimidazolium Acetate/Water Mixtures – Part 2" Z. Phys. Chem. 2013, 227, 177–203. (51 citations*, DOI `10.1524/zpch.2012.0327` ) ⭳Bib
12	O. Hollóczki, D. S. Firaha, J. Friedrich, M. Brehm, R. Cybik, M. Wild, A. Stark, B. Kirchner: "Carbene Formation in Ionic Liquids: Spontaneous, Induced, or Prohibited?" J. Phys. Chem. B 2013, 117 (19), 5898–5907. (108 citations, DOI `10.1021/jp4004399` ) ⭳Bib
10	M. Brüssel, M. Brehm, A. S. Pensado, F. Malberg, M. Ramzan, A. Stark, B. Kirchner: "On the Ideality of Binary Mixtures of Ionic Liquids" Phys. Chem. Chem. Phys. 2012, 14, 13204–13215. (94 citations, DOI `10.1039/C2CP41926B` ) ⭳Bib
9	K. Wendler, M. Brehm, F. Malberg, B. Kirchner, L. Delle Site: "Short Time Dynamics of Ionic Liquids in AIMD-Based Power Spectra" J. Chem. Theory Comput. 2012, 8 (5), 1570–1579. (74 citations*, DOI `10.1021/ct300152t` ) ⭳Bib
8	M. Brehm, H. Weber, A. S. Pensado, A. Stark, B. Kirchner: "Proton Transfer and Polarity Changes in Ionic Liquid–Water Mixtures: A Perspective on Hydrogen Bonds from ab initio Molecular Dynamics at the Example of 1-Ethyl-3-Methylimidazolium Acetate–Water Mixtures—Part 1" Phys. Chem. Chem. Phys. 2012, 14, 5030–5044. (141 citations*, DOI `10.1039/C2CP23983C` ) ⭳Bib
7	A. S. Pensado, M. Brehm, J. Thar, A. P. Seitsonen, B. Kirchner: "Effect of Dispersion on the Structure and Dynamics of the Ionic Liquid 1-Ethyl-3-Methylimidazolium Thiocyanate" ChemPhysChem 2012, 13 (7), 1845–1853. (82 citations*, DOI `10.1002/cphc.201100917` ) ⭳Bib
4	M. Brüssel, M. Brehm, T. Voigt, B. Kirchner: "Ab initio Molecular Dynamics Simulations of a Binary System of Ionic Liquids" Phys. Chem. Chem. Phys. 2011, 13, 13617–13620. (71 citations*, DOI `10.1039/C1CP21550G` ) ⭳Bib
1	J. Thar, M. Brehm, A. P. Seitsonen, B. Kirchner: "Unexpected Hydrogen Bond Dynamics in Imidazolium-Based Ionic Liquids" J. Phys. Chem. B 2009, 113 (46), 15129–15132. (115 citations*, DOI `10.1021/jp908110j` ) ⭳Bib