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TlF is TlF-II structured and crystallizes in the orthorhombic Pbcm space group. The structure is two-dimensional and consists of one TlF sheet oriented in the (0, 0, 1) direction. Tl1+ is bonded in a 5-coordinate geometry to five equivalent F1- atoms. There are a spread of Tl–F bond distances ranging from 2.50–3.40 Å. F1- is bonded in a 4-coordinate geometry to five equivalent Tl1+ atoms.
TlF is gamma CuTi structured and crystallizes in the tetragonal P4/nmm space group. The structure is two-dimensional and consists of one TlF sheet oriented in the (0, 0, 1) direction. Tl1+ is bonded to five equivalent F1- atoms to form a mixture of distorted edge and corner-sharing TlF5 square pyramids. There are one shorter (2.49 Å) and four longer (2.79 Å) Tl–F bond lengths. F1- is bonded to five equivalent Tl1+ atoms to form a mixture of distorted edge and corner-sharing FTl5 trigonal bipyramids.
TlF is gamma CuTi structured and crystallizes in the orthorhombic Pma2 space group. The structure is two-dimensional and consists of one TlF sheet oriented in the (0, 0, 1) direction. there are two inequivalent Tl1+ sites. In the first Tl1+ site, Tl1+ is bonded to five F1- atoms to form a mixture of distorted corner and edge-sharing TlF5 square pyramids. There are a spread of Tl–F bond distances ranging from 2.49–2.92 Å. In the second Tl1+ site, Tl1+ is bonded to five F1- atoms to form a mixture of distorted corner and edge-sharing TlF5 square pyramids. There are a spread of Tl–F bond distances ranging from 2.49–2.94 Å. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded to five Tl1+ atoms to form a mixture of distorted corner and edge-sharing FTl5 trigonal bipyramids. In the second F1- site, F1- is bonded to five Tl1+ atoms to form a mixture of distorted corner and edge-sharing FTl5 trigonal bipyramids.
TlF is Halite, Rock Salt structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Tl1+ is bonded to six equivalent F1- atoms to form a mixture of corner and edge-sharing TlF6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Tl–F bond lengths are 2.84 Å. F1- is bonded to six equivalent Tl1+ atoms to form a mixture of corner and edge-sharing FTl6 octahedra. The corner-sharing octahedral tilt angles are 0°.
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The Cold molecule Nuclear Time-Reversal EXperiment (CeNTREX) is a new effort aiming for a significant increase in sensitivity over the best present upper bounds on the strength of hadronic time reversal (T) violating fundamental interactions. The experimental signature will be shifts in nuclear magnetic resonance frequencies of 205 Tl in electrically-polarized thallium fluoride (TlF) molecules. Here we describe the motivation for studying these T-violating interactions and for using TlF to do so. To achieve higher sensitivity than earlier searches for T-violation in TlF, CeNTREX uses a cryogenic molecular beam source, optical state preparation and detection, and modern methods of coherent quantum state manipulation. Details of the measurement scheme and the current state of the apparatus are presented, with quantitative measurements of the TlF beam. Lastly, the estimated sensitivity and methods to control systematic errors are discussed.
The formation and evolution of the Solar System is closely related to the abundance of volatiles, namely water, ammonia, and methane in the protoplanetary disk. Accurate measurement of volatiles in the Solar System is therefore important to understand not only the nebular hypothesis and origin of life but also planetary cosmogony as a whole. In this work, we propose a new, remote sensing technique to infer the outer planets water content by measuring Tremendously and Extremely Low Frequency (TLF-ELF) electromagnetic wave characteristics (Schumann resonances) excited by lightning in their gaseous envelopes. Schumann resonance detection can be potentially used for constraining the uncertainty of volatiles of the giant planets, mainly Uranus and Neptune, because such TLF-ELF wave signatures are closely related to the electric conductivity profile and water content.
PbO is TlF-II structured and crystallizes in the orthorhombic Pbcm space group. The structure is two-dimensional and consists of one PbO sheet oriented in the (0, 0, 1) direction. Pb2+ is bonded in a distorted rectangular see-saw-like geometry to four equivalent O2- atoms. There are a spread of Pb–O bond distances ranging from 2.26–2.51 Å. O2- is bonded in a distorted see-saw-like geometry to four equivalent Pb2+ atoms.
PbO is TlF-II structured and crystallizes in the orthorhombic Pca2_1 space group. The structure is two-dimensional and consists of one PbO sheet oriented in the (0, 0, 1) direction. Pb2+ is bonded in a distorted T-shaped geometry to three equivalent O2- atoms. There are one shorter (2.25 Å) and two longer (2.26 Å) Pb–O bond lengths. O2- is bonded in a trigonal planar geometry to three equivalent Pb2+ atoms.
The current capabilities of relativistic electronic structure codes for calculations on molecules such as TlF and YbF, which are of interest in the study of parity non-conservation, will be presented. The issues of basis set size and correlation methods will be discussed, and planned developments of the codes which would extend the range of their capabilities will be outlined. Issues of the sensitivity of the desired properties to the form of the nuclear potential and the flexibility of the wave function near the nucleus will be raised to stimulate discussion.