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P2O9 is Silicon tetrafluoride-like structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of eight phosphoric acid molecules and four water molecules.
TlC4(N2S)4PO4 crystallizes in the orthorhombic Cccm space group. The structure is one-dimensional and consists of four phosphoric acid molecules and two TlC4(N2S)4 ribbons oriented in the (0, 0, 1) direction. In each TlC4(N2S)4 ribbon, Tl3+ is bonded in a body-centered cubic geometry to eight S2- atoms. There are four shorter (3.03 Å) and four longer (3.05 Å) Tl–S bond lengths. There are two inequivalent C4+ sites. In the first C4+ site, C4+ is bonded in a distorted trigonal planar geometry to two equivalent N1- and one S2- atom. Both C–N bond lengths are 1.31 Å. The C–S bond length is 1.83 Å. In the second C4+ site, C4+ is bonded in a distorted trigonal planar geometry to two equivalent N1- and one S2- atom. Both C–N bond lengths are 1.31 Å. The C–S bond length is 1.84 Å. There are two inequivalent N1- sites. In the first N1- site, N1- is bonded in a single-bond geometry to one C4+ and one S2- atom. The N–S bond length is 3.35 Å. In the second N1- site, N1- is bonded in a single-bond geometry to one C4+ atom. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to two equivalent Tl3+ and one C4+ atom. In the second S2- site, S2- is bonded in a 3-coordinate geometry to two equivalent Tl3+, one C4+, and two equivalent N1- atoms.
Al2(PO6)3PO4 is Molybdenum Carbide MAX Phase-like structured and crystallizes in the trigonal R3 space group. The structure is zero-dimensional and consists of three phosphoric acid molecules and three Al2(PO6)3 clusters. In each Al2(PO6)3 cluster, there are two inequivalent Al sites. In the first Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with three equivalent PO4 tetrahedra. There is three shorter (1.82 Å) and three longer (1.94 Å) Al–O bond length. In the second Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with three equivalent PO4 tetrahedra. There is three shorter (1.86 Å) and three longer (1.93 Å) Al–O bond length. P is bonded to four O atoms to form PO4 tetrahedra that share corners with two AlO6 octahedra. The corner-sharing octahedra tilt angles range from 26–32°. There are a spread of P–O bond distances ranging from 1.52–1.57 Å. There are six inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Al atom. In the second O site, O is bonded in a single-bond geometry to one Al atom. In the third O site, O is bonded in a bent 150 degrees geometry to one Al and one P atom. In the fourth O site, O is bonded in a bent 150 degrees geometry to one Al and one P atom. In the fifth O site, O is bonded in a single-bond geometry to one P atom. In the sixth O site, O is bonded in a single-bond geometry to one P atom.
CrO6PO4 is Silicon tetrafluoride-derived structured and crystallizes in the monoclinic Cc space group. The structure is zero-dimensional and consists of eight phosphoric acid molecules and eight CrO6 clusters. In each CrO6 cluster, Cr is bonded in a tetrahedral geometry to four O atoms. There are a spread of Cr–O bond distances ranging from 1.62–1.75 Å. There are six inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Cr atom. In the second O site, O is bonded in a bent 120 degrees geometry to two O atoms. There is one shorter (1.21 Å) and one longer (1.77 Å) O–O bond length. In the third O site, O is bonded in a single-bond geometry to one Cr and one O atom. In the fourth O site, O is bonded in a single-bond geometry to one Cr atom. In the fifth O site, O is bonded in a single-bond geometry to one O atom. In the sixth O site, O is bonded in a single-bond geometry to one Cr atom.
(K(PO4)3)2(N2)3(PO4)2 crystallizes in the tetragonal P-4 space group. The structure is three-dimensional and consists of three ammonia molecules, one phosphoric acid molecule, and one K(PO4)3 framework. In the K(PO4)3 framework, K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are four shorter (2.89 Å) and four longer (2.98 Å) K–O bond lengths. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded in a tetrahedral geometry to four equivalent O2- atoms. All P–O bond lengths are 1.54 Å. In the second P5+ site, P5+ is bonded in a tetrahedral geometry to four O2- atoms. There is two shorter (1.53 Å) and two longer (1.55 Å) P–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one K1+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one K1+ and one P5+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one P5+ atom.
PO4 is Silicon tetrafluoride-like structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four phosphoric acid molecules. P is bonded in a tetrahedral geometry to four O atoms. All P–O bond lengths are 1.54 Å. There are four inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one P atom. In the second O site, O is bonded in a single-bond geometry to one P atom. In the third O site, O is bonded in a single-bond geometry to one P atom. In the fourth O site, O is bonded in a single-bond geometry to one P atom.
RhO6PO4 crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of eight phosphoric acid molecules and eight RhO6 clusters. In each RhO6 cluster, Rh is bonded in a distorted octahedral geometry to six O atoms. All Rh–O bond lengths are 1.93 Å. There are three inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Rh atom. In the second O site, O is bonded in a single-bond geometry to one Rh atom. In the third O site, O is bonded in a single-bond geometry to one Rh atom.
(Mo2P2O13)4(N2)4PO4N4Br crystallizes in the tetragonal P-4 space group. The structure is two-dimensional and consists of eight ammonia molecules; one phosphoric acid molecule; one N4Br cluster; and two Mo2P2O13 sheets oriented in the (0, 0, 1) direction. In the N4Br cluster, N is bonded in a single-bond geometry to one Br atom. The N–Br bond length is 2.17 Å. Br is bonded in a rectangular see-saw-like geometry to four equivalent N atoms. In each Mo2P2O13 sheet, there are two inequivalent Mo sites. In the first Mo site, Mo is bonded to six O atoms to form distorted MoO6 octahedra that share a cornercorner with one MoO6 octahedra and corners with three PO4 tetrahedra. The corner-sharing octahedral tilt angles are 26°. There are a spread of Mo–O bond distances ranging from 1.73–2.24 Å. In the second Mo site, Mo is bonded to six O atoms to form distorted MoO6 octahedra that share a cornercorner with one MoO6 octahedra and corners with three PO4 tetrahedra. The corner-sharing octahedral tilt angles are 27°. There are a spread of Mo–O bond distances ranging from 1.75–2.32 Å. There are two inequivalent P sites. In the first P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with three MoO6 octahedra. The corner-sharing octahedra tilt angles range from 17–48°. There is two shorter (1.54 Å) and two longer (1.55 Å) P–O bond length. In the second P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with three MoO6 octahedra. The corner-sharing octahedra tilt angles range from 34–48°. There are a spread of P–O bond distances ranging from 1.53–1.55 Å. There are fourteen inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to two equivalent Mo atoms. In the second O site, O is bonded in a single-bond geometry to one Mo atom. In the third O site, O is bonded in a distorted single-bond geometry to one Mo and one P atom. In the fourth O site, O is bonded in a distorted bent 150 degrees geometry to one Mo and one P atom. In the fifth O site, O is bonded in a distorted linear geometry to one Mo and one P atom. In the sixth O site, O is bonded in a distorted single-bond geometry to one Mo and one P atom. In the seventh O site, O is bonded in a single-bond geometry to one Mo atom. In the eighth O site, O is bonded in a bent 150 degrees geometry to one Mo and one P atom. In the ninth O site, O is bonded in a single-bond geometry to one Mo atom. In the tenth O site, O is bonded in a bent 150 degrees geometry to two equivalent Mo atoms. In the eleventh O site, O is bonded in a 1-coordinate geometry to one Mo and one P atom. In the twelfth O site, O is bonded in a single-bond geometry to one P atom. In the thirteenth O site, O is bonded in a single-bond geometry to one Mo atom. In the fourteenth O site, O is bonded in a single-bond geometry to one P atom.
CrO6PO4 is Silicon tetrafluoride-derived structured and crystallizes in the monoclinic Cc space group. The structure is zero-dimensional and consists of eight phosphoric acid molecules and eight CrO6 clusters. In each CrO6 cluster, Cr is bonded in a distorted tetrahedral geometry to six O atoms. There are a spread of Cr–O bond distances ranging from 1.61–2.39 Å. There are six inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Cr atom. In the second O site, O is bonded in a single-bond geometry to one Cr atom. In the third O site, O is bonded in a distorted single-bond geometry to one Cr atom. In the fourth O site, O is bonded in a single-bond geometry to one Cr atom. In the fifth O site, O is bonded in a single-bond geometry to one Cr atom. In the sixth O site, O is bonded in a single-bond geometry to one Cr atom.
H3PO3 crystallizes in the monoclinic P2_1 space group. The structure is one-dimensional and consists of four phosphorous acid molecules and two H3PO3 ribbons oriented in the (0, 1, 0) direction. In each H3PO3 ribbon, P5+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is one shorter (1.61 Å) and two longer (1.64 Å) P–O bond length. There are three inequivalent H+0.33+ sites. In the first H+0.33+ site, H+0.33+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the second H+0.33+ site, H+0.33+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.70 Å) H–O bond length. In the third H+0.33+ site, H+0.33+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.01 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one P5+ and one H+0.33+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one P5+ and one H+0.33+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one P5+ and two H+0.33+ atoms.
Na4AsH29O18HPO4 crystallizes in the monoclinic Pc space group. The structure is one-dimensional and consists of two phosphoric acid molecules and two Na4AsH29O18 ribbons oriented in the (0, 1, 0) direction. In each Na4AsH29O18 ribbon, there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six O2- atoms to form a mixture of edge and face-sharing NaO6 octahedra. There are a spread of Na–O bond distances ranging from 2.38–2.47 Å. In the second Na1+ site, Na1+ is bonded to six O2- atoms to form a mixture of edge and face-sharing NaO6 octahedra. There are a spread of Na–O bond distances ranging from 2.39–2.46 Å. In the third Na1+ site, Na1+ is bonded to six O2- atoms to form a mixture of edge and face-sharing NaO6 octahedra. There are a spread of Na–O bond distances ranging from 2.34–2.48 Å. In the fourth Na1+ site, Na1+ is bonded to six O2- atoms to form a mixture of edge and face-sharing NaO6 octahedra. There are a spread of Na–O bond distances ranging from 2.34–2.48 Å. As5+ is bonded in a tetrahedral geometry to four O2- atoms. There is three shorter (1.71 Å) and one longer (1.78 Å) As–O bond length. There are twenty-nine inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the ninth H1+ site, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.02 Å) and one longer (1.60 Å) H–O bond length. In the tenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the eleventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the twelfth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the thirteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the fourteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the fifteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the sixteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the seventeenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the eighteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the nineteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the twentieth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the twenty-first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the twenty-second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the twenty-third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the twenty-fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the twenty-fifth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the twenty-sixth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the twenty-seventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the twenty-eighth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the twenty-ninth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one As5+ atom. In the second O2- site, O2- is bonded in a distorted water-like geometry to one Na1+ and two H1+ atoms. In the third O2- site, O2- is bonded in a distorted water-like geometry to one Na1+ and two H1+ atoms. In the fourth O2- site, O2- is bonded in a distorted water-like geometry to one Na1+ and three H1+ atoms. In the fifth O2- site, O2- is bonded in a distorted water-like geometry to one Na1+ and two H1+ atoms. In the sixth O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the seventh O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to one As5+ atom. In the ninth O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the tenth O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the eleventh O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the twelfth O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the thirteenth O2- site, O2- is bonded in a single-bond geometry to one As5+ atom. In the fourteenth O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the fifteenth O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the sixteenth O2- site, O2- is bonded in a 2-coordinate geometry to one As5+ and one H1+ atom. In the seventeenth O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the eighteenth O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms.
TlP2(NO4)2PO4 crystallizes in the tetragonal I-42d space group. The structure is three-dimensional and consists of four phosphoric acid molecules and one TlP2(NO4)2 framework. In the TlP2(NO4)2 framework, Tl1+ is bonded to eight O2- atoms to form distorted TlO8 hexagonal bipyramids that share corners with four equivalent PO4 tetrahedra and edges with two equivalent PO4 tetrahedra. There are four shorter (2.99 Å) and four longer (3.02 Å) Tl–O bond lengths. P5+ is bonded to four O2- atoms to form distorted PO4 tetrahedra that share corners with two equivalent TlO8 hexagonal bipyramids and an edgeedge with one TlO8 hexagonal bipyramid. There is two shorter (1.47 Å) and two longer (1.82 Å) P–O bond length. N4+ is bonded in a water-like geometry to two equivalent O2- atoms. Both N–O bond lengths are 1.31 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Tl1+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted L-shaped geometry to one Tl1+, one P5+, and one N4+ atom.
(WO3)12((CH3)2NH2)3PO4 crystallizes in the trigonal R-3m space group. The structure is zero-dimensional and consists of eighteen dimethylazanium molecules, six phosphoric acid molecules, and six WO3 clusters. In each WO3 cluster, there are three inequivalent W sites. In the first W site, W is bonded in a 5-coordinate geometry to five O atoms. There is one shorter (1.73 Å) and four longer (1.95 Å) W–O bond length. In the second W site, W is bonded in a 5-coordinate geometry to five O atoms. There are a spread of W–O bond distances ranging from 1.74–1.95 Å. In the third W site, W is bonded in a 5-coordinate geometry to five O atoms. There are a spread of W–O bond distances ranging from 1.74–1.95 Å. There are nine inequivalent O sites. In the first O site, O is bonded in a bent 120 degrees geometry to two equivalent W atoms. In the second O site, O is bonded in a bent 150 degrees geometry to two equivalent W atoms. In the third O site, O is bonded in a bent 120 degrees geometry to two equivalent W atoms. In the fourth O site, O is bonded in a bent 150 degrees geometry to two W atoms. In the fifth O site, O is bonded in a single-bond geometry to one W atom. In the sixth O site, O is bonded in a single-bond geometry to one W atom. In the seventh O site, O is bonded in a bent 120 degrees geometry to two W atoms. In the eighth O site, O is bonded in a bent 150 degrees geometry to two equivalent W atoms. In the ninth O site, O is bonded in a single-bond geometry to one W atom.
CrO6CrO4(PO4)2O2 is Silicon tetrafluoride-derived structured and crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of four cq4 molecules, four oxygen molecules, eight phosphoric acid molecules, and four CrO6 clusters. In each CrO6 cluster, Cr is bonded in an octahedral geometry to six O atoms. There is four shorter (1.81 Å) and two longer (1.83 Å) Cr–O bond length. There are three inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Cr atom. In the second O site, O is bonded in a single-bond geometry to one Cr atom. In the third O site, O is bonded in a single-bond geometry to one Cr atom.
Direct-emitting red and amber LEDs based on the AlInGaP material system offer a higher efficacy potential than phosphor-converted (pc) red and amber LEDs due to the absence of Stokes losses. Direct red LEDs (~610-620nm) are increasingly used in color-mixed and color-tunable illumination applications, where they have a significant advantage over pc-red LEDs, with high power conversion efficiency (PCE) and narrower emission enabling higher luminous efficacy of radiation (LER). Still, adoption is limited as the complexities associated with mixing different emitters offset the value of the efficacy gain. Adoption of direct amber LEDs (~580-595nm) in illumination applications is virtually non-existent due to their lower PCE and the availability of very efficient pc-amber emitters, which suffer less from Stokes loss and LER penalties associated with the broader bandwidth than pc-red. Further improvement in PCE of direct red and amber LEDs is needed to achieve wider adoption and ultimately enable more energy savings than possible with pc-LEDs. In this project, Lumileds has developed improved high-power amber and red LEDs incorporating tensile-strain barriers into the active region to improve carrier confinement and thereby increase external quantum efficiency (EQE). This approach is most beneficial for the short (amber) end of the AlInGaP wavelength range where carrier confinement is lowest. An EQE of 22% was achieved for amber LEDs, exceeding the project target of 20%
Electropolishing of uranium metal is best performed in a simple aqueous solution of phosphoric acid. With +3 to +10 volts of bias potential applied to the uranium (anode) relative to a Pt counter electrode (cathode). As summarized in a Pourbaix stability diagram, these conditions yield dissolution of the U surface as UOX containing solution species without the possibility of injecting hydrogen into the metal surface. However, if the uranium is biased to negative potentials relative to the counter electrode then water may be reduced at the U surface and hydrogen gas becomes available for reaction with the U metal. The stability diagram may be modified if there are other complexing species present in solution and the potential scale shifted if a different metal is use for the counter electrode. These effects can be understood in a known way as long as solution and electrochemical cell conditions are recognized.
The Compact Electron Permanent Magnet Spectrometer (CEPMS) shown in Figure 2 consists of collimation at the electron beam entrance, a vacuum chamber for beam transport and a removable 60 degree sector magnet constructed by SABR Enterprises (Ref 2) that is used to momentum analyze the incoming electron beam. There are electron detection planes located perpendicular to straight through and the 60 degree trajectory ports. The planes are designed to accept phosphor screens for time integrated measurements. The screens can be replaced by scintillator for time resolved measurements using gated or streak cameras. The length of the spectrometer along the beamline without the collimator is about 400mm (14”). The spectrometer requires no power supply with controls for cycling or cooling for the magnet. The entire assembly, with magnet installed, weighs about 35kg (75lbs) Figure 3 depicts central and extreme trajectories through the spectrometer for various electron energies. The chamber accommodates a +/-50mm wide detection field relative to the center trajectory. Trajectories with larger momentum (energy) are bent the least. Since the permanent magnet slides off and on with reference to the upstream edge of the vacuum chamber, it can be adjusted to various positions to slightly increase or decrease the central energy thereby changing the range of available energies. Figure 4 shows the effect of changing the location of the permanent magnet on the electron trajectory. A small inward change in r produces a longer trajectory in the magnet therefore, the same energy trajectory is bent more.
The electronic structure and ultrafast (10-15 s-femtosecond timescale) electron dynamics were investigated for clean and atom/molecule covered metal surfaces. The studies were performed by scanning tunneling microscopy (STM) to measure the structure of adsorbed atoms and molecules on metal surfaces, and to investigate their electronic properties. The electronic structure of the observed molecular networks was calculated by electronic structure theory in collaboration with Prof. Jin Zhao, who is a long-time collaborator, a Professor at the University of Science and Technology of China, and holds an Adjunct Professorship at the University of Pittsburgh. We also investigated the electronic properties of C60 molecules when they are templated by corrugated black phosphorous surfaces. We found unexpected charge delocalization that is enabled by the templating. This research was done in collaboration with Professor Min Feng at the Wuhan University, and who also holds an Adjunct Professorship at the University of Pittsburgh. Moreover, the electronic structure and electron dynamics in metal surfaces were investigated by time-resolved photoemission electron spectroscopy. The focus of ultrafast spectroscopy has been on the plasmonic response of silver surfaces. One direction has been to develop multidimensional (energy, momentum, and time) photoelectron spectroscopy of the coherent response of solid surfaces. This method was applied to study the collective electron excitations known generally as plasmons, which screen optical fields from penetration into metals. Although this collective response has been known for more than 60 years and is used extensively to deposit optical energy into metals, how this happens is poorly known. We investigated the plasmonic response of silver at the point where the dielectric response passes through zero and bulk plasmon is excited by light. We discovered that the plasmon excitation decays by exciting electrons from the Fermi level of a metal, which is contrary to what is believed in the plasmonic science community. This research has been performed in collaboration with Dr. Marcel Reutzel, who was a postdoctoral fellow working on this research at the University of Pittsburgh, and now has a faculty position at the University of Göttingen in Germany. Prof. Branko Gumhalter from the Institute of Physics in Zagreb contributed on the theory of plasmonic decay processes. Furthermore, we investigated the Floquet engineering of electronic bands in metals leading to multiphoton photoemission and above threshold photoemission. Finally, we demonstrated that it is possible to change the electronic structure of metals by application of optical fields. Our studies indicated that this happens on subfemtosecond time scale and could potentially be used in ultrafast information processing and quantum computation. Related document information