Sorbonne-Univ./CNRS

Laboratoire de chimie de la matière condensée de Paris
Tour 44-43 / 4ème étage
Case courrier 174
4, Place Jussieu
75005 PARIS
France

Pr. Christian BONHOMME

Professeur
SMiLES

christian.bonhomme(@-Code a retirer pour éviter le SPAM-)sorbonne-universite.fr

Christian Bonhomme is a chemical engineer from the Ecole Nationale Supérieure de Chimie de Paris (ENSCP) and graduated in 1990. He defended his doctoral thesis in 1994 under the supervision of Pr J. Livage. During the last year of his thesis he was interested more particularly in solid state NMR methods and in cross-polarization under fast MAS, then a central topic in the NMR community. Assistant Professor in 1994, he spent his entire career at the Laboratoire de Chimie de la Matière Condensée de Paris (LCMCP) at Sorbonne University, Paris, France. He is currently full Professor (exceptionnal class 2 – highest level in France). From 2009 to 2011 he was Visiting Professor at the Physics Department of the University of Warwick, UK (SOME REFS). He has established a very strong collaboration with several English colleagues and is a regular user of the NMR UK national facility [ref]. He has established numerous national and international collaborations: TO COMPLETE (people + 1 ref…).

He has presented §§ invited national and international conferences, most recently PANACEA (September 2024, Aveiro, Portugal), §§§§. Lectures cover both solid state NMR and DNP applied to the study of materials, and mathematical developments related to spin dynamics and associated numerical methods. Among §§§ articles and abstracts, he is the author of §§ reviews in NMR applications in materials science [Accounts Chem Res 2007-Progress NMR 2014-SSNMR 2020], DFT calculations of NMR parameters [Chem rev 2012-Book 2014] and data treatment [GUL].

Currently, his scientific topics of interest are: (1) NMR/DNP [1-2-3] including methodology for non-sensitive nuclei such as 43Ca and 17O [2017+…]; (2) Instrumentation & signal processing [4-5]; (3) DFT, ab initio calculations of NMR parameters, NMR crystallography & MD simulations [6-7,8]; (4) Applications in materials science including synthetic [§§] and natural biomaterials such as pathological calcifications (kidney stones) [9-10]; (5) Precipitation in confined media [§§§]; (6) Graph theory & Path-Sum for Quantum Mechanics/spin dynamics in NMR/DNP [11].

During the first years of his career, he trained himself in the theoretical aspects of solid-state NMR and was able to propose in 1998 an original mathematical description of the macroscopic reorientations of the sample in NMR, generalizing to upper ranks the ellipsoid representation traditionally used in physics for the description of rank 2 tensors [12-13-14]. In his HDR (Habilitation à Diriger des Recherches) defended in 2003, he proposes in conclusion to include Feynman paths in spin dynamics. He concretizes this proposal in 2020 [11] in very close collaboration with P.-L. Giscard, mathematician at Université du Littoral Côte d’Opale, Calais, France. In this context, he is also working with S. Pozza – a specialist in matrix calculus at Charles University, Prague, Czech Republic, on ultra-fast codes for solving systems of coupled linear differential equations (related to spin dynamics) [§§].

[1] C. Bonhomme, C. Gervais, D. Laurencin, Prog. Nucl. Magn. Reson. Spectr., 77, 1-48 (2014). [2] C. Leroy, F. Aussenac, L. Bonhomme-Coury, A. Osaka, S. Hayakawa, F. Babonneau, C. Coelho-Diogo, C. Bonhomme, Analytical Chem., 89, 10201-10207 (2017). [3] D. Lee, C. Leroy, C. Crevant, L. Bonhomme-Coury, F. Babonneau, D. Laurencin, C. Bonhomme, G. De Paëpe, Nature Commun., 8, 14104 (2017). [4] A. Lehmann-Horn, J.-F. Jacquinot, J. C. Ginefri, C. Bonhomme, D. Sakellariou, J. Magn. Reson., 271, 46‑51 (2016). [5] G. Laurent, W. Woelffel, V. Barret-Vivin, E. Gouillart, and C. Bonhomme, Appl. Spectrosc. Rev., 54, 602-630 (2019). [6] C. Bonhomme, C. Gervais, C. Coelho, F. Pourpoint, T. Azaïs, F. Babonneau, S. Ashbrook, J. Griffin, J. Yates, C. J. Pickard, F. Mauri, Chemical Reviews, 112, 5733-5779 (2012). [7] C. Bonhomme, C. Gervais, N. Folliet, F. Pourpoint, C. Coelho-Diogo, J. Lao, E. Jallot, J. Lacroix, J.M. Nedelec, D. Iuga, J.V. Hanna, M.E. Smith, Y. Xiang, J. Du, D. Laurencin, J. Am. Chem. Soc., 134(30), 12611‑12628 (2012). [8] C. Bonhomme, X.L. Wang, I. Hung, Z.H. Gan, C. Gervais, C .Sassoye, J. Rimsza, J.C. Du, M.E. Smith, J.V. Hanna, S. Sarda, P. Gras, C. Combes, D. Laurencin, Chemical Commun. 54, 9591‑9594 (2018). [9] L. Mayen, N. D. Jensen, D. Laurencin, O. Marsan, C. Bonhomme, C. Gervais, M. E. Smith, C. Coelho, G. Laurent, J. Trebosc, Z. Gan, K. Chen, C. Rey, C. Combes, J. Soulie, Acta Biomaterialia, 103, 333-345 (2020). [10] C. Gervais, C. Bonhomme, D. Laurencin, Solid State NMR, 2020, 107:101663. [11] P.‑L. Giscard, C. Bonhomme, Phys. Rev. Res., 2, 023081 (2020). [12] C. Bonhomme, J. Livage, J. Phys. Chem. A, 103, 460-477 (1999). [13] C. Bonhomme, J. Livage, J. Phys. Chem. A, 102, 375-385 (1998). [13] C. Bonhomme, T. Azaïs, C.R. Chimie, 7, 417-424 (2004).

1- Towards an « Infinite » Number of Calcium Oxalate Structures? (IUCr, 2023, Melbourne, Australia) – KEYNOTE speaker

2- Path-Sum: a New Avenue for Spin Dynamics (43rd FGMR Annual Discussion Meeting, 2022) – PLENARY speaker

3- New Potentialities of NMR and DNP for the Study of Biomaterials: Experiments and Theory (Experimental Nuclear Magnetic Resonance Conference, 2022) – INVITED speaker


Solid state NMR

CP dynamics including Inversion Recovery Cross Polarization (IRCP) is an invaluable tool of investigation for the detailed study of local dynamics (Chem. Mater. 1996, 8, 1415-1428) including unexpected molecular reorientation « at the Magic Angle » in some silsesquioxanes (J. Chem. Soc. Dalton Trans. 1997, 1617-1626; J. Am. Chem. Soc. 1998, 120, 8380-8391) and distance measurements in multiple-spin systems (Solid State NMR 2005, 28, 50-56). Halogen NMR such as 35Cl at various (high) magnetic fields is a useful spectroscopic probe for OH…Cl hydrogen bond in static and (moderate) MAS modes (Solid State NMR 2003, 23, 14-27). 

Solid state NMR methodology is developed in the framework of J-derived techniques under fast MAS in connection with the first principles calculations of J couplings by GIPAW (Inorg. Chem. 2007, 46, 1379‑1387; Accounts Chem. Res. 2007, 40, 738-746), exotic non sensitive nuclei such 43Ca and 87Sr (J. Am. Chem. Soc. 2009, 131, 13430-13440; J. Am. Chem. Soc. 2012, 134, 12611-12628), ultra-broad spectra (ChemistrySelect 2016, 4509-4519) and ultra-high magnetic field: 35.1 T, 1.5 GHz (Chem. Commun. 2018, 69, 9591-9594).

A/ Ultra-high resolution 43Ca MAS spectra for calcium pyrophosphates and oxalate obtained at ultra-high magnetic field (35.1 T, 1.5 GHz) at NHMFL, Tallahassee, FL, USA. Dashed lines correspond to GIPAW calculations. Adapted from Chem. Commun. 2018, 69, 9591-9594. B/ 1H-13C-43Ca TRADOR experiments related to tri-hydrated calcium benzoate *Ca(C6H5COO)2.3H2O at 9.4 T, 400 MHz, partially labeled in 43Ca. Adapted from J. Am. Chem. Soc. 2009, 131, 13430-13440.

DNP (Dynamic Nuclear Polarization)

DNP has revolutionalized the description of carbonated hydroxyapatite (Analytical Chem. 2017, 89, 10201-10207). 1H-1H spin diffusion is quasi one-dimensional along the OH– columns (parallel to the c-axis). Local order and clustering of the carbonate anions is clearly demonstrated by 13C-13C homonuclear correlation MAS DNP experiments. The clusters of carbonates are located in zig-zag chains along the c-axis of the structure. The DNP enhancement is sufficient to implement 1H-43Ca HETCOR experiments in natural abundance which is a true challenge for this nucleus (0.14% and low gamma) (Nature Commun. 2017, 8, 14104).

A/ Schematic representation of the hydroxyapatite structure partially substituted by carbonate anions (black triangle in the OH– column). During DNP, the protons at the surface of the nanoparticles are first hyperpolarized. Then the polarization is transported by spin diffusion along the columns in a quasi one-dimensional process. Adapted from Analytical Chem. 2017, 89, 10201-10207. B/ The first 1H-43Ca HETCOR CP MAS DNP experiment in natural abundance (43Ca: 0.14%) obtained in 4 hours. Adapted from Nature Commun. 2017, 8, 14104.

Instrumentation

Sensitivity remains the main drawback of NMR. Following Sakellariou et al., MACS (Magic Angle Coil Spinning) is a perfect alternative for samples characterized by a low mass (such as biological samples). The solenoid geometry for the microcoil is among the most versatile ones, is suitable for microfabrication (PLOS ONE 2012, 7, e42848) reaching an enhancement of 5-10 in certain cases. Recently, monolithic MACS microresonators were developed for high resolution NMR keeping intact the intrinsic cylindrical symmetry of the set-up and allowing for fast MAS (J. Magn .Reson. 2016, 271, 46-51).

A/ Magic Angle Coil SPinning (MACS) concept developed by Sakellariou et al. Microfabricated solenoid microcoils. Adapted from PLOS ONE 2012, 7, e42848. B/ Monolithic MACS resonators used for MACS applications. Adapted from J. Magn. Reson. 2016, 271, 46-51.

Signal processing

Major improvement has been obtained in the denoising of time-domain signal by using Singular Value Decomposition (SVD) accelarated by Graphics Processing Units (GPU) (Solid State NMR 2014, 61-62, 28-34). (J. Magn .Reson. 2016, 271, 46-51). SVD limits have been deeply investigated recently (Appl. Spectr. Rev. 2019, 54, 602-630). A 100 gain in time was achieved by combining divide and conquer algorithm, Intel Math Kernel Library (MKL), SSE3 (Streaming SIMD Extensions) hardware instructions and single precision. In such case, the CPU can outperform the GPU driven by CUDA technology. (Appl. Spectr. Rev. 2020, 55, 173-196).

A/ Denoising (Cadzow) procedure. Hankel matrix H contains the digitised noisy time-domain signal. Σ1,2,3 correspond to the singular values. Adapted from Solid State NMR 2014, 61-62, 28-34. B/ Influence of the number of columns (n) for Toeplitz FID matrix construction for a 29Si CPMG solid state NMR spectrum of 50/50 MTEOS/TEOS (CH3Si(OEt)3/Si(OEt)4) sample. Adapted from Appl. Spectr. Rev. 2019, 54, 602-630.

First principles calculations of NMR parameters, NMR crystallography

Following the pionneering work of Pickard and Mauri (2001), first principles calculations of NMR parameters were systematically implemented in the case of molecular inorganic (Magn. Res .Chem. 2004, 42, 445-452; J. Am. Chem. Soc. 2010, 132, 4653-4668; J. Am. Chem. Soc. 2012, 134, 12611-12628) and organic solids (J. Phys. Chem. A 2005, 109, 6960-6969), biocompatible materials (App. Magn. Res. 2007, 32, 435-457; CrystEngComm 2013, 15, 8840-8847; Acta Biomater. 2016, 31, 348-357), molecular dynamics (Phys. Chem. Chem. Phys. 2009, 11, 6953-6961) and non crystalline solids (J. Am. Chem. Soc. 2012, 134, 12611-12628; Chem. Commun. 2018, 54, 9591-9594). For a review article: Chem. Reviews 2012, 112, 5733-5779.

A/ MD simulations of amorphous calcium pyrophosphate glasses (a-CPP) for various level of hydration (n), 43Ca MAS NMR spectrum at ultra-high magnetic field (35.1 T) and associated 43Ca isotropic chemical shifts calculated by GIPAW. Adapted from Chem. Commun 2018, 54, 9591-9594. B/ Correlation between the computed 43Ca isotropic chemical shifts and the mean Ca. . .O bond distance in various calcium pyrophosphates, depending on the Ca coordination number (CN) and the number of water molecules in the coordination sphere. Adapted from Acta Biomater. 2016, 31, 348-357.

Applications in materials science

We focus here on our latest interest in soft-chemistry applied to the systhesis of amorphous calcium ortho/pyrophosphate biomaterials of tunable composition (Acta Biomater. 2020, 103, 333-345) and more generally to advanced NMR methods applied to the characterization of biocompatible materials (Solid State NMR, 2020, 107:101663).

A/ 31P SQ-DQ spectrum of ortho/pyrophosphate glass acquired at 16.4 T, spinning at 14 kHz. The dashed red boxes show the cross-peaks between ortho and pyrophosphate units. B/ 23Na-31 P D-HMQC spectrum (heteronuclear dipolar correlation) of ortho/pyrophosphate glass, acquired at 18.8 T using 20 kHz spinning speed (the 23Na NMR spectra in blue and red correspond to correlations with pyro- and orthophosphate ions, respectively). Adapted from Acta Biomater. 2020, 103, 333-345.

Quantum mechanics and Path-Sum

In collaboration with P.-L. Giscard, we have applied the Path-Sum concept to NMR for the first time solving analytically the Bloch-Siegert effect at all order (avoiding perturbative treatments), spin diffusion in an organimetallic molecule exhibiting 42 protons and giving entirely new insight in Coherent Destruction of Tuneling, CDT (ENC 2019, Asilomar, USA; Phys. Rev. Res., 2020, 2, 023081). We recently solved the Bloch equations in their most general form (ENC 2020, Baltimore, Zoom conference, USA).

A/ The dynamical graph associated to the time-dependent matrix A(t). Adapted from ENC, 2019, Asilomar, USA. B/ Path-Sum applied to Bloch-Siegert effect from weak- to ultra-strong coupling. Adapted from Phys. Rev. Res. 2020, 2, 023081.
  1. Solid state NMR (Master, Sorbonne University)
  2. Solid state NMR tutorials (Master, Sorbonne University)
  3. NMR exams (Master, Sorbonne University)
  4. Characterization of biological materials (Master, Sorbonne University)
  5. Silicon: from periodic table to biogenic silica (BSc, Sorbonne University)
  6. Zeolites and porous structures (BSc, Sorbonne University)
  7. Introduction to spectroscopy (BSc, Sorbonne University)
  8. Introduction to thermal analyses (BSc, Sorbonne University)

Starting in 1946

  1. DNP/NMR @ LCMCP: instrumentation, beyond standard GIPAW and applications to biomaterials (4th sino-french workshop, 2017, Wuhan, China)
  2. Solid state NMR: new trends in materials science (2nd Edition of the International Summer School Physical and Chemical Principles in Materials Science, 2016, Paris, France)
  3. Principes de base en Résonance Magnétique Nucléaire (Ecole thématique Magnétisme et Résonances Magnétiques : Outils et Applications, 2015, Autrans, France,).