The group is active along the following research lines
a) Molecular crystal polymorphism, investigation of crystallization
and nucleation conditions of new polymorphic, co-crystals, and
solvate forms of organic and inorganic molecular crystals. This
research line includes some co-operative efforts and contracts with
drug companies.
b) Design and preparation and characterization of hydrogen bonded
hybrid inorganic-organometallic acid salts for application in solid
fuel cell technology and investigation of the theoretical aspects
of hydrogen bonding between and with ionic systems
c) Design, synthesis and characterization of organometallic
building blocks for the preparation of superstructures based on
heterometallic systems and for the engineering of network
structures. The organometallic synthesis is carried out in Braga's
prep lab.
d) Solvent-free reactions: here we explore both solid-gas reactions
involving an organometallic solid substrate that reversibly absorbs
and releases small molecules
e) Mechanochemically activated reactions between crystals or within
crystals to form new crystalline materials or new molecular
products in solvent-free conditions
f) Preparation of ionic and molecular co-crystals (Fabrizia
Grepioni)
g) Preparation of supramolecular gels and investigation of their
photochemical properties (Fabrizia Grepioni)
h) Synthesis and photochemical properties of clusters based on the
CuI framework (Lucia Maini)
i) Structural determination from powder diffraction data
In 2005 Braga's Group launched a spinoff company
(PolyCrystalLine, PCL s.r.l.) in the field of solid state chemistry
and crystal polymorphism. The company is fully independent and
employs several chemists from Braga's lab. PCL and Braga's
research group now constitute a fully integrated knowledge-transfer
system able to meet the demand of high tech research outsourcing
from materials, chemical and pharmaceutical industries.
Crystal forms (Polymorphs, Solvates, Co-crystals and Ionic
Co-crystals) Design, synthesis, solid-state properties of
new crystal forms (polymorphs, solvates, molecular and ionic
co-crystals, salts and coordination compounds with
biocompatible metals) of organic molecules of pharmaceutical and
agrochemical interest. Supramolecular gels
Supramolecular (super)gelators based on coordination
compounds of d-block elements, to be used as media for
crystallization of small molecules.
Metal-Organic Frameworks (MOFs) are compounds based on a
3D structure in which nodes, made by metal ions (or metal ions
clusters), are linked by organic bridging ligands. The structure
itself is made by channels, which can be connected one to each
others and gives the possibility to small molecules to be embedded
in. MOF could be luminescence, such as the MOFs we are interested
in, and the luminescence could be temperature depending and can be
tuned depending on the ligand used and the crystallographic node
properties. MOFs, in general, can satisfy a variety of needs in
technological field such as luminescence for optical devices, drug
delivery for pharmaceutical aims, catalysis and chemical
sensors.
Photoluminescent solids. Tuning of the luminescence
properties of molecular solids via co-crystallization. The targets
are (i) the synthesis of phosphorent only-organic solid-state
materials and (ii) the enhancement of photoluminescence response
for applications in photovoltaic cells.
Crystal Engineering of molecular solids to be employed as
sensors for X-ray radiation. Functionalization of organic
semiconductors, with the aim of organizing the molecules in the
solid-state to maximize the electric response to X-ray irradiation.
A detailed knowledge of packing features and intermolecular
interactions are essental for this task.
