About

Brian Space is a professor in the Department of Chemistry at NC State University. He holds a B.A. in Physical Chemistry from Boston University (1988), a Ph.D. in Physical Chemistry from Boston University (1992), and completed postdoctoral research at NSF CISE Princeton University in 1995. His research group specializes in developing and applying models of porous materials and interfacial systems, with a particular emphasis on theoretical modeling of Metal Organic Materials. The group is actively engaged in collaborative work with international materials synthesis and characterization groups. Additionally, his research focuses on improving simulations, leading to the development of modern PHAST force fields for atomistic modeling of materials. Dr. Space has received numerous awards and significant grant funding from organizations including NSF, NIST, the American Chemical Society, the U.S. Department of Energy, and NASA.

Research topics

• Chemistry
• Organic chemistry
• Chemical engineering
• Materials science
• Composite material
• Crystallography
• Physical chemistry

Selected publications

• A permanently porous chalcogen-bonded organic framework

  Nature Synthesis · 2026-05-15

  article
  PublisherDOI

• Harnessing cooperative sorbate-sorbent adaptation in a flexible metal-organic framework for switchable hydrocarbon separation

  Science Advances · 2026-03-25 · 1 citations

  articleOpen access

  The pursuit of selective adsorption for separating molecules with similar shapes and interactions remains a formidable challenge. This work harnesses a powerful, previously unrecognized mechanism in a flexible metal-organic framework (Flex-Cd-MOF-3) to achieve switchable adsorption selectivity. Specifically, Flex-Cd-MOF-3, a descendant of Flex-Cd-MOF-2 with increased linker rigidity and functionalization, exhibits both local rearrangements and reversible framework expansion or shrinkage, showing phase-dependent propylene/propane selectivity. Considering propane, mutually beneficial conformational changes in the material and sorbate co-occur that are not possible with rigid propylene, reshaping the energy landscapes. These distinct interaction mechanisms, for otherwise very similar molecules, directly lead to pore swelling and shrinking at different pressures and phase switchable selectivity. An innovative modeling approach was developed that describes the full desorption pathway, explaining the relative binding energies and the sorbate-dependent mechanism of pore shrinkage. This work establishes cooperative sorbate-sorbent adaptation as a generalizable adsorption mechanism for achieving precise separation of similar molecules through distinct intermolecular interactions.

  PublisherDOI

• The PHAST 2.0 Force Field for General Small Molecule and Materials Simulations

  Journal of Chemical Theory and Computation · 2025-06-03 · 2 citations

  articleSenior authorCorresponding

  Classical, empirical molecular simulation has become increasingly important in chemistry due to its ability to accurately model and resolve experimental phenomena on the atomic scale. Still, many challenges remain including obtaining subkilojoules per mole accuracy while maintaining speed, computational efficiency, and transferability to novel and heterogeneous chemistries. Further, a distinct lack of systematic progress on force fields over the last decades is shown to be due to a lack of a comprehensive, systematic approach rather than inherent deficiencies in rationally chosen potential energy surfaces. Indeed, to achieve these goals, it has become necessary to move beyond the highly approximate mean field Lennard-Jones equation, which is the backbone of many modern general purpose force fields. Lennard-Jones based force fields are both state point dependent and overfit to a large number of atom types to try and reproduce bulk thermophysical benchmarks; this fitting comes at the cost of physical grounding and transferability. Here, a new general purpose force field, PHAST 2.0, is presented where the parameters are fit solely to electronic structure data; PHAST is validated on the same kinds of experimental bulk data with which current Lennard-Jones based force fields are parametrized. PHAST has the emergent property of generality and transferability that is aided by including explicit many-body polarization. It is also designed to work with many-body dispersion models in a modular fashion. Being constructed from the fundamental interactions allows for force field elaboration for specific molecules or materials of interest without reparametrization. Several atom typing schemes, as well as an implicit polarization version, are explored. PHAST 2.0 has accuracy in line with the best common general purpose force fields used today with very minimal atom typing and thermodynamic state point independence, maintaining reduced complexity and enhanced transferability. It is argued this approach leads straightforwardly to bespoke, one-off PHAST force fields for a chemistry of interest, where additional training is warranted for additional accuracy.

  PublisherDOI

• PHAST-MBD: Implementing Many-Body Dispersion in the PHAST 2.0 Potential, Results for Noble Gases

  Journal of Chemical Theory and Computation · 2025-06-10

  articleSenior authorCorresponding

  A recently published empirical force field (herein PHAST or PHAST 2.0) is employed in its many-body dispersion-corrected form (PHAST-MBD) to examine the effects of collective dispersion interactions. Rare gases are used as a systematic way to test increasing importance of van der Waals attractions in systems dominated by repulsion-dispersion that are a challenge to extant force fields. The effects of many-body dispersion were studied for liquid and supercritical fluid regime for the series Neon, Argon, Krypton and Xenon. The PHAST force field is a condensed phase atomistic molecular modeling potential that includes contributions from repulsion-dispersion, permanent electrostatics, and many-body polarization. Each of these pieces is physics based and seeks to mimic their constituent first-principles counterparts with as few fitting parameters as possible. Critically, it is built to reproduce accurate gas phase pair interactions. This facilitates the efficacy of mixing rules for unlike interactions while many-body effects are added via explicit polarization and dispersion models. The effectiveness of PHAST-MBD is demonstrated calculating rare gas densities as compared to experiment over a wide pressure range. Pair potentials fail systematically at high pressure and density as dispersion grows while PHAST-MBD reproduces experiment in all regimes. This is strong evidence in favor of the PHAST 2.0 paradigm of physically motivated empirical potentials that reproduce gas phase interactions and facilitate accurate mixing rules with many-body effects included explicitly. This work suggests a hybrid future approach that will be adopted in PHAST-MBD that keeps the accurate PHAST pair interactions and only includes many-body terms via the coupled dipole method (CDM); such an approach avoids the issues identified here that the CDM many body van der Waals (MBVDWs) formalism has reasonable but nonoptimal implicit mixing rules and can alter pair potentials.

  PublisherDOI

• A Permanently Porous Chalcogen-Bonded Organic Framework with an Unprecedented Ensemble of Adsorption, Assembly, Dynamics, and Electronic Properties

  ChemRxiv · 2025-10-07

  article

  The nature of connectivity between constituent atomic or molecular building blocks is fundamental in shaping the properties and functionality of materials. Indeed, the extrapolation of emergent interatomic interactions to enable functional materials has driven transformative technological advancements. However, the toolbox of bonding interactions employed in material design has remained largely static since the emergence of dynamic covalent chemistry some 30 years ago. Here, we demonstrate that noncovalent chalcogen bonding (Ch-bonding) is a fundamentally new mode of interatomic connectivity for constructing functional materials by design. This is demonstrated by leveraging the high-fidelity, self-complementary assembly of 1,2,5-telluradiazole moieties to construct a honeycomb-type permanently porous chalcogen-bonded organic framework (ChOF), assembled and stabilized solely through noncovalent Te···N contacts. Empirical and computational studies of gas adsorption, structural healing, lattice dynamics, and electronic structure reveal an unprecedented collection of attributes arising directly from the unique nature of the Te···N Ch-bonding. In addition to introducing a distinct class of permanently porous frameworks, this work reveals Ch-bonding to be an emergent and unique tool for the construction of functional materials with never-before-seen ensembles of properties and behaviors.

  PublisherDOI

• Combining Theory and Experiment to Map the Atomic-Level Structure–Energy Pathways of Adsorbate-Mediated Phase Changes in a Cooperatively Flexible Metal–Organic Framework

  Journal of the American Chemical Society · 2025-06-11 · 5 citations

  articleSenior authorCorresponding

  An important subclass of metal–organic frameworks (MOFs) exhibits cooperative flexibility, wherein individual crystallites undergo global structural phase changes in response to external stimuli. Where cooperative flexibility results in reversible changes between crystalline states of distinct accessible porosity, these frameworks can exhibit rare yet desirable behaviors that cannot be explained by local dynamics alone. Yet, the chemical and structural origins of cooperative flexibility and how frameworks undergo these reversible phase changes at the atomic level remain poorly understood. Deliberate design for specific applications is therefore exceedingly difficult, and there is great impetus to develop a fundamental understanding of this phenomenon. Here, an effective and widely accessible computational approach is developed, which is designed to provide microscopic resolution via direct comparison to experimental data along the desorption-guided pathway. The strategy is applied to explain the desorption-induced phase change in an experimentally well-characterized framework, CdIF-13 (sod-Cd(benzimidazolate)2), where experiment alone was unable to resolve the atomistically detailed phase change landscape. Our findings reveal that the cooperative phase change pathways are adsorbate dependent with thermodynamics of intermediate structural states dictated by a nuanced interplay of ligand orientation, skeletal symmetry, and modes of surface adsorption. The results reveal that this isotropically flexible framework is “chaperoned” through a complex energy landscape by specific adsorbates, revealed by the reported computational approach with atomic-level insight and validated by experimentally determined structures. Thus, this work facilitates both understanding and future design of flexible materials for applications in gas storage, transport, delivery, and separation technologies.

  PublisherDOI

• Chalcogen Bonding as a Design Paradigm for Functional Materials

  ChemRxiv · 2025-10-27

  article

  The nature of connectivity between constituent atomic or molecular building blocks is fundamental in shaping the properties and functionality of materials. Indeed, the extrapolation of emergent interatomic interactions to enable functional materials has driven transformative technological advancements. However, the toolbox of bonding interactions employed in material design has been largely static since the emergence of dynamic covalent chemistry some 30 years ago. Here, we demonstrate that noncovalent chalcogen bonding (Ch-bonding) is a fundamentally distinct mode of interatomic connectivity for constructing functional materials by design. This is demonstrated by leveraging the high-fidelity, self-complementary assembly of 1,2,5-telluradiazole moieties to construct a honeycomb-type permanently porous chalcogen-bonded organic framework (ChOF), assembled and stabilized solely through noncovalent Te···N contacts. Empirical and computational studies of electronic structure, structural healing, and lattice dynamics reveal an unprecedented collection of attributes with significant implications for next generation crystalline semiconductors arising directly from the unique nature of the Te···N Ch-bonding. In addition to introducing a distinct class of permanently porous frameworks, this work establishes Ch-bonding as a programmable molecular tool for the construction of healable functional materials with never-before-seen properties.

  PublisherDOI

• An Ultramicroporous Physisorbent Sustained by a Trifecta of Directional Supramolecular Interactions

  Journal of the American Chemical Society · 2025-01-02 · 12 citations

  articleOpen access

  2D and 3D porous coordination networks (PCNs) as exemplified by metal–organic frameworks, MOFs, have garnered interest for their potential utility as sorbents for molecular separations and storage. The inherent modularity of PCNs has enabled the development of crystal engineering strategies for systematic fine-tuning of pore size and chemistry in families of related PCNs. The same cannot be said about one-dimensional (1D) coordination polymers, CPs, which are understudied with respect to porosity. Here, we report that permanent porosity is exhibited by the previously reported family of linear (L) 1D porous CPs, PCPs, of formula [M(bipy)(NO3)2(H2O)2]n (L-chn-1-M-NO3: M = Co, Ni; bipy = 4,4′-bipyridine). Their pore structure comprises 1D channels sustained by three types of directional interaction: coordination bonds; hydrogen bonds; offset π–π interactions. Heating L-chn-1-M-NO3 in vacuo or above 383 K resulted in removal of the aqua ligands and concomitant transformation to nonporous anhydrate phases ZZ-chn-1-Co-NO3 (ZZ = zigzag) and HT-Ni. Exposure of these anhydrate phases to ambient humidity resulted in regeneration of L-chn-1-M-NO3. That L-chn-1-M-NO3 exhibits permanent porosity was supported by CO2 and water sorption measurements, which afforded reversible type I and stepped (S-shaped) isotherm profiles, respectively, making this work the first demonstration of reversible water sorption in a 1D PCP. The water sorption properties are pertinent to atmospheric water harvesting: onset of uptake at ca. 12% relative humidity; activation required only mild heat or vacuum; relatively fast adsorption/desorption kinetics; performance retained over >100 adsorption/desorption cycles. We project water harvesting productivity of L-chn-1-M-NO3 of 3.3 L kg–1 d–1, on par with some leading MOF desiccants. DFT and Monte Carlo simulations provide insights into the structure of water molecules in the channels, provide their influence on the host framework, and provide a plausible argument for the experimental water vapor isotherms. This work demonstrates that easily scalable 1D PCPs, a potentially vast class of materials, can exhibit porous structures sustained by three types of directional supramolecular synthons and offer desirable water sorption properties.

  PublisherDOI

• A Propeller-Like Ligand-Directed Construction of a Tetranuclear Cerium-Organic Framework for Single-Step Ethylene Purification from Ternary C₂ Mixtures

  Inorganic Chemistry · 2024-07-23 · 3 citations

  article

  The efficient single-step purification of ethylene from ternary C2 mixtures containing ethane and acetylene is challenging and demanding. Herein, we introduce a novel cerium-based metal–organic framework (MOF) of Ce-NTB-rtk synthesized via a ligand-conformer strategy. The Ce-NTB-rtk features a rare tetranuclear cerium cluster and 2D kgd layers pillared by a 3D rtl framework concomitant with an extraordinary (3,3,12)-c network. The compound encompasses microporous cavities replete with a nonpolar microenvironment. Gas sorption and breakthrough experiments demonstrate its superior affinity for C2H6 and C2H2 over C2H4, enabling effective single-step ethylene purification. Computational simulations reveal that preferential adsorptions are facilitated by different interaction strengths of C–H···O hydrogen bonds. The performance of Ce-NTB-rtk in separation selectivity and regeneration capacity makes it a promising candidate for sustainable and cost-effective ethylene purification, showcasing the potential of MOFs in advanced gas separation applications.

  PublisherDOI

• PHAHST Potential: Modeling Sorption in a Dispersion-Dominated Environment

  Journal of Chemical Theory and Computation · 2024-06-18 · 4 citations

  articleSenior authorCorresponding

  PHAHST (potentials with high accuracy, high speed, and transferability) is a recently developed force field that utilizes exponential repulsion, multiple dispersion terms, explicit many-body polarization, and many-body van der Waals interactions. The result is a systematic approach to force field development that is computationally practical. Here, PHAHST is employed in the simulation for rare gas uptake of krypton and xenon in the metal-organic material, HKUST-1. This material has shown promise in use as an adsorptive separating agent and presents a challenge to model due to the presence of heterogeneous interaction sorption surfaces, which include pores with readily accessible, open-metal sites that compete with dispersion-dominated pores. Such environments are difficult to simulate with commonly used empirical force fields, such as the Lennard-Jones (LJ) potential, which perform better when electrostatics are dominant in determining the nature of sorption and alone are incapable of modeling interactions with open-metal sites. The effectiveness of PHAHST is compared to the LJ potential in a series of mixed Kr-Xe gas simulations. It has been demonstrated that PHAHST compares favorably with experimental results, and the LJ potential is inadequate. Overall, we establish that force fields with physically grounded repulsion/dispersion terms are required in order to accurately model sorption, as these interactions are an important component of the energy. Furthermore, it is shown that the simple mixing rules work nearly quantitatively for the true pair potentials, while they are not transferable for effective potentials like LJ.

  PublisherDOI

Recent grants

• Modeling of Metal Organic Materials (MOMs): Force Field Innovations and Applications with Impact

  NSF · $420k · 2016–2020

• U.S.-Ireland R&D Partnership: AQUASORB: Predictive Modeling of Atmospheric Water Sorption

  NSF · $450k · 2023–2027

• Theoretical Investigations of the Spectroscopy and the Associated Structure and Dynamics of Liquids and Their Interfaces

  NSF · $345k · 2003–2007

• Molecularly Detailed Theories of Interfaces: Spectroscopy and Sorption

  NSF · $417k · 2012–2016

Frequent coauthors

• Tony Pham

  University of South Florida

  190 shared

• Katherine A. Forrest

  North Carolina State University

  161 shared

• Michael J. Zaworotko

  University of Limerick

  86 shared

• Juergen Eckert

  39 shared

• Douglas Franz

  University of South Florida

  32 shared

• Sameh K. Elsaidi

  Illinois Institute of Technology

  31 shared

• Mona H. Mohamed

  Alexandria University

  31 shared

• Adam Hogan

  North Carolina State University

  30 shared

Labs

• Chemistry LabPI

Education

• Ph.D., Chemistry

  University of North Carolina at Chapel Hill

  2002

• M.S., Chemistry

  University of North Carolina at Chapel Hill

  1998

• B.S., Chemistry

  University of North Carolina at Chapel Hill

  1996

Awards & honors

• NSF CAREER Award
• AAAS Fellow