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Yb2Cl2F is alpha Niobium phosphide-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is zero-dimensional and consists of one Yb2Cl2F cluster. Yb is bonded in a linear geometry to one Cl and one F atom. The Yb–Cl bond length is 2.43 Å. The Yb–F bond length is 2.15 Å. Cl is bonded in a single-bond geometry to one Yb atom. F is bonded in a linear geometry to two equivalent Yb atoms.
Na2LiS2 is alpha Niobium phosphide-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is zero-dimensional and consists of one Na2LiS2 cluster. Na1+ is bonded in a single-bond geometry to one S+1.50- atom. The Na–S bond length is 2.47 Å. Li1+ is bonded in a linear geometry to two equivalent S+1.50- atoms. Both Li–S bond lengths are 2.28 Å. S+1.50- is bonded in a linear geometry to one Na1+ and one Li1+ atom.
Ba2Cl2F is alpha Niobium phosphide-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is zero-dimensional and consists of one Ba2Cl2F cluster. Ba is bonded in a linear geometry to one Cl and one F atom. The Ba–Cl bond length is 2.72 Å. The Ba–F bond length is 2.50 Å. Cl is bonded in a single-bond geometry to one Ba atom. F is bonded in a linear geometry to two equivalent Ba atoms.
Ba2HCl2 is alpha Niobium phosphide-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is zero-dimensional and consists of one Ba2HCl2 cluster. Ba is bonded in a linear geometry to one H and one Cl atom. The Ba–H bond length is 2.53 Å. The Ba–Cl bond length is 2.71 Å. H is bonded in a linear geometry to two equivalent Ba atoms. Cl is bonded in a single-bond geometry to one Ba atom.
Eu2Br2F is alpha Niobium phosphide-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is zero-dimensional and consists of one Eu2Br2F cluster. Eu is bonded in a linear geometry to one Br and one F atom. The Eu–Br bond length is 2.70 Å. The Eu–F bond length is 2.32 Å. Br is bonded in a single-bond geometry to one Eu atom. F is bonded in a linear geometry to two equivalent Eu atoms.
CoN5Cl2NO2 is alpha Niobium phosphide structured and crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of four nitrous acid molecules and four CoN5Cl2 clusters. In each CoN5Cl2 cluster, Co2+ is bonded in a single-bond geometry to three N+0.67+ atoms. There is one shorter (1.59 Å) and two longer (1.95 Å) Co–N bond length. There are three inequivalent N+0.67+ sites. In the first N+0.67+ site, N+0.67+ is bonded in a single-bond geometry to one Cl1- atom. The N–Cl bond length is 1.51 Å. In the second N+0.67+ site, N+0.67+ is bonded in a 2-coordinate geometry to one Co2+ and one Cl1- atom. The N–Cl bond length is 1.53 Å. In the third N+0.67+ site, N+0.67+ is bonded in a single-bond geometry to one Co2+ atom. Cl1- is bonded in a bent 120 degrees geometry to two N+0.67+ atoms.
Yb2Br2F is alpha Niobium phosphide-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is zero-dimensional and consists of one Yb2Br2F cluster. Yb is bonded in a linear geometry to one Br and one F atom. The Yb–Br bond length is 2.58 Å. The Yb–F bond length is 2.13 Å. Br is bonded in a single-bond geometry to one Yb atom. F is bonded in a linear geometry to two equivalent Yb atoms.
NbCl5P4Se3 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of eight niobium(v) chloride molecules and eight tetraphosphorous triselenide molecules.
MnH30(CN)6(Se)4 is alpha Niobium phosphide structured and crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of four MnH30(CN)6 clusters and four Se clusters. In each MnH30(CN)6 cluster, Mn2+ is bonded to six N3- atoms to form MnN6 octahedra that share corners with six CH3N tetrahedra. There are a spread of Mn–N bond distances ranging from 2.31–2.36 Å. There are three inequivalent C1- sites. In the first C1- site, C1- is bonded to one N3- and three H1+ atoms to form CH3N tetrahedra that share a cornercorner with one MnN6 octahedra. The corner-sharing octahedral tilt angles are 60°. The C–N bond length is 1.48 Å. All C–H bond lengths are 1.10 Å. In the second C1- site, C1- is bonded to one N3- and three H1+ atoms to form CH3N tetrahedra that share a cornercorner with one MnN6 octahedra. The corner-sharing octahedral tilt angles are 59°. The C–N bond length is 1.48 Å. All C–H bond lengths are 1.10 Å. In the third C1- site, C1- is bonded to one N3- and three H1+ atoms to form CH3N tetrahedra that share a cornercorner with one MnN6 octahedra. The corner-sharing octahedral tilt angles are 58°. The C–N bond length is 1.48 Å. All C–H bond lengths are 1.10 Å. There are three inequivalent N3- sites. In the first N3- site, N3- is bonded in a 4-coordinate geometry to one Mn2+, one C1-, and two H1+ atoms. Both N–H bond lengths are 1.03 Å. In the second N3- site, N3- is bonded in a 4-coordinate geometry to one Mn2+, one C1-, and two H1+ atoms. There is one shorter (1.03 Å) and one longer (1.04 Å) N–H bond length. In the third N3- site, N3- is bonded in a 4-coordinate geometry to one Mn2+, one C1-, and two H1+ atoms. There is one shorter (1.02 Å) and one longer (1.03 Å) N–H bond length. There are fifteen inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one C1- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one C1- atom. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one C1- atom. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one C1- atom. In the ninth H1+ site, H1+ is bonded in a single-bond geometry to one C1- atom. In the tenth H1+ site, H1+ is bonded in a single-bond geometry to one C1- atom. In the eleventh H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the twelfth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the thirteenth H1+ site, H1+ is bonded in a single-bond geometry to one C1- atom. In the fourteenth H1+ site, H1+ is bonded in a single-bond geometry to one C1- atom. In the fifteenth H1+ site, H1+ is bonded in a single-bond geometry to one C1- atom. In each Se cluster, there are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a bent 120 degrees geometry to two Se2- atoms. There are one shorter (2.38 Å) and one longer (2.39 Å) Se–Se bond lengths. In the second Se2- site, Se2- is bonded in a single-bond geometry to one Se2- atom.
Sr2Cl2F is alpha Niobium phosphide-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is zero-dimensional and consists of one Sr2Cl2F cluster. Sr is bonded in a linear geometry to one Cl and one F atom. The Sr–Cl bond length is 2.56 Å. The Sr–F bond length is 2.31 Å. Cl is bonded in a single-bond geometry to one Sr atom. F is bonded in a linear geometry to two equivalent Sr atoms.
NbO2VO2 is Protactinium-derived structured and crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of two niobium;dihydrate molecules and two vanadium;dihydrate molecules.
(Cd)2CdSe is alpha Niobium phosphide-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is two-dimensional and consists of two Cd sheets oriented in the (0, 0, 1) direction and two CdSe sheets oriented in the (0, 0, 1) direction. In each Cd sheet, Cd is bonded in a square co-planar geometry to four equivalent Cd atoms. All Cd–Cd bond lengths are 2.89 Å. In each CdSe sheet, Cd is bonded in a square co-planar geometry to four equivalent Se atoms. All Cd–Se bond lengths are 2.89 Å. Se is bonded in a square co-planar geometry to four equivalent Cd atoms.
Bi20(PtI12)3 is alpha Niobium phosphide-derived structured and crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of one Bi20(PtI12)3 cluster. there are two inequivalent Pt2- sites. In the first Pt2- site, Pt2- is bonded in an octahedral geometry to six Bi+2.10+ atoms. There are four shorter (2.76 Å) and two longer (2.77 Å) Pt–Bi bond lengths. In the second Pt2- site, Pt2- is bonded in an octahedral geometry to six Bi+2.10+ atoms. There are a spread of Pt–Bi bond distances ranging from 2.76–2.78 Å. There are ten inequivalent Bi+2.10+ sites. In the first Bi+2.10+ site, Bi+2.10+ is bonded to one Pt2- and four I1- atoms to form BiPtI4 square pyramids that share a cornercorner with one BiPtI4 square pyramid, an edgeedge with one BiI6 octahedra, and edges with four BiPtI4 square pyramids. There are a spread of Bi–I bond distances ranging from 3.10–3.28 Å. In the second Bi+2.10+ site, Bi+2.10+ is bonded to one Pt2- and four I1- atoms to form BiPtI4 square pyramids that share a cornercorner with one BiPtI4 square pyramid, an edgeedge with one BiI6 octahedra, and edges with four BiPtI4 square pyramids. There are two shorter (3.11 Å) and two longer (3.28 Å) Bi–I bond lengths. In the third Bi+2.10+ site, Bi+2.10+ is bonded to one Pt2- and four I1- atoms to form BiPtI4 square pyramids that share a cornercorner with one BiPtI4 square pyramid, an edgeedge with one BiI6 octahedra, and edges with four BiPtI4 square pyramids. There are a spread of Bi–I bond distances ranging from 3.03–3.42 Å. In the fourth Bi+2.10+ site, Bi+2.10+ is bonded to one Pt2- and four I1- atoms to form BiPtI4 square pyramids that share a cornercorner with one BiPtI4 square pyramid, an edgeedge with one BiI6 octahedra, and edges with four BiPtI4 square pyramids. There are a spread of Bi–I bond distances ranging from 3.04–3.40 Å. In the fifth Bi+2.10+ site, Bi+2.10+ is bonded to one Pt2- and four I1- atoms to form a mixture of corner and edge-sharing BiPtI4 square pyramids. There are a spread of Bi–I bond distances ranging from 3.08–3.27 Å. In the sixth Bi+2.10+ site, Bi+2.10+ is bonded to one Pt2- and four I1- atoms to form a mixture of corner and edge-sharing BiPtI4 square pyramids. There are a spread of Bi–I bond distances ranging from 3.10–3.23 Å. In the seventh Bi+2.10+ site, Bi+2.10+ is bonded to six I1- atoms to form edge-sharing BiI6 octahedra. There are a spread of Bi–I bond distances ranging from 3.05–3.21 Å. In the eighth Bi+2.10+ site, Bi+2.10+ is bonded to one Pt2- and four I1- atoms to form BiPtI4 square pyramids that share a cornercorner with one BiPtI4 square pyramid, an edgeedge with one BiI6 octahedra, and edges with four BiPtI4 square pyramids. There are a spread of Bi–I bond distances ranging from 3.10–3.28 Å. In the ninth Bi+2.10+ site, Bi+2.10+ is bonded to one Pt2- and four I1- atoms to form BiPtI4 square pyramids that share a cornercorner with one BiPtI4 square pyramid, an edgeedge with one BiI6 octahedra, and edges with four BiPtI4 square pyramids. There are a spread of Bi–I bond distances ranging from 3.03–3.41 Å. In the tenth Bi+2.10+ site, Bi+2.10+ is bonded to one Pt2- and four I1- atoms to form a mixture of corner and edge-sharing BiPtI4 square pyramids. There are a spread of Bi–I bond distances ranging from 3.08–3.26 Å. There are eighteen inequivalent I1- sites. In the first I1- site, I1- is bonded in a distorted L-shaped geometry to two Bi+2.10+ atoms. In the second I1- site, I1- is bonded in a distorted L-shaped geometry to two Bi+2.10+ atoms. In the third I1- site, I1- is bonded in a distorted T-shaped geometry to three Bi+2.10+ atoms. In the fourth I1- site, I1- is bonded in a 3-coordinate geometry to three Bi+2.10+ atoms. In the fifth I1- site, I1- is bonded in a 3-coordinate geometry to three Bi+2.10+ atoms. In the sixth I1- site, I1- is bonded in a 3-coordinate geometry to three Bi+2.10+ atoms. In the seventh I1- site, I1- is bonded in a 2-coordinate geometry to two Bi+2.10+ atoms. In the eighth I1- site, I1- is bonded in a distorted L-shaped geometry to two Bi+2.10+ atoms. In the ninth I1- site, I1- is bonded in a 2-coordinate geometry to two Bi+2.10+ atoms. In the tenth I1- site, I1- is bonded in a distorted L-shaped geometry to two Bi+2.10+ atoms. In the eleventh I1- site, I1- is bonded in a distorted L-shaped geometry to two Bi+2.10+ atoms. In the twelfth I1- site, I1- is bonded in a distorted L-shaped geometry to two Bi+2.10+ atoms. In the thirteenth I1- site, I1- is bonded in a distorted T-shaped geometry to three Bi+2.10+ atoms. In the fourteenth I1- site, I1- is bonded in a 3-coordinate geometry to three Bi+2.10+ atoms. In the fifteenth I1- site, I1- is bonded in a 2-coordinate geometry to two Bi+2.10+ atoms. In the sixteenth I1- site, I1- is bonded in a 2-coordinate geometry to two Bi+2.10+ atoms. In the seventeenth I1- site, I1- is bonded in a distorted L-shaped geometry to two Bi+2.10+ atoms. In the eighteenth I1- site, I1- is bonded in a distorted L-shaped geometry to two Bi+2.10+ atoms.
Yb2OBr2 is alpha Niobium phosphide-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is zero-dimensional and consists of one Yb2OBr2 cluster. Yb2+ is bonded in a linear geometry to one O2- and one Br1- atom. The Yb–O bond length is 2.06 Å. The Yb–Br bond length is 2.66 Å. O2- is bonded in a linear geometry to two equivalent Yb2+ atoms. Br1- is bonded in a single-bond geometry to one Yb2+ atom.
NbF5NHNHO crystallizes in the monoclinic C2 space group. The structure is zero-dimensional and consists of four ammonia molecules, four niobium pentafluoride molecules, and four nitroxyl molecules.
Eu2Cl2F is alpha Niobium phosphide-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is zero-dimensional and consists of one Eu2Cl2F cluster. Eu is bonded in a linear geometry to one Cl and one F atom. The Eu–Cl bond length is 2.55 Å. The Eu–F bond length is 2.33 Å. Cl is bonded in a single-bond geometry to one Eu atom. F is bonded in a linear geometry to two equivalent Eu atoms.
Superconducting radio-frequency niobium cavities are susceptible to deformations caused by external or internal forces, leading to shifts in the cavity resonant frequency. One source of deformation comes from the radiation pressure of the cavity fields, producing the so-called Lorentz force detuning effect. This effect can couple to the cavity mechanical modes in generator driven mode, leading to ponderomotive instability. In the FRIB 322 MHz, β=0.53 Half-wave Resonators (HWR), the instability appeared when the cavity was detuned, with thresholds depending on low-level RF control parameters, such as closed loop gain, as well as accelerating gradient. Using a measured Lorentz Transfer Function, Simulink simulations were conducted to predict the instability thresholds, which were then compared with the experimental results. We will discuss how these thresholds can be broadened to enable stable operation at higher gradients.
Nb₃Sn is a prospective material for future superconducting RF (SRF) accelerator cavities. The material can achieve higher quality factors, higher temperature operation and potentially higher accelerating gradients (E_{acc} 96 MV/m) compared to conventional niobium. In this work, we performed modeling of the Upgraded Injector Test Facility (UITF) at Jefferson Lab utilizing newly constructed Nb₃Sn cavities. We studied the effects of the buncher cavity and varied the gun voltages from 200-500 keV. We have calibrated and optimized the SRF cavity gradients and phases for the Nb₃Sn five-cell cavities energy gains with the framework of General Particle Tracer (GPT). Our calculations show the beam goes cleanly through the unit. There is full energy gain out of the second SRF cavity but not from the first SRF cavity due to non-relativistic phase shifts.