Per-Olov Löwdin

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Per-Olov Löwdin is affiliated with the following schools: Uppsala University, University of Florida

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Per-Olov Löwdin

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Physics

Per-Olov Löwdin's Degrees

PhD Theoretical Physics Uppsala University

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According to Wikipedia, Per-Olov Löwdin was a Swedish physicist, professor at the University of Uppsala from 1960 to 1983, and in parallel at the University of Florida until 1993. A former graduate student under Ivar Waller, Löwdin formulated in 1950 the symmetric orthogonalization scheme for atomic and molecular orbital calculations, greatly simplifying the tight-binding method. This scheme is the basis of the zero-differential overlap approximation used in semiempirical theories. In 1956 he introduced the canonical orthogonalization scheme, which is optimal for eliminating approximate linear dependencies of a basis set. These orthogonalization procedures are widely used today in all modern quantum chemistry calculations.

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Per-Olov Löwdin's Published Works

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Published Works

On the Non‐Orthogonality Problem Connected with the Use of Atomic Wave Functions in the Theory of Molecules and Crystals (1950) (2458)
Quantum Theory of Many-Particle Systems. I. Physical Interpretations by Means of Density Matrices, Natural Spin-Orbitals, and Convergence Problems in the Method of Configurational Interaction (1955) (2404)
Quantum Theory of Many-Particle Systems. III. Extension of the Hartree-Fock Scheme to Include Degenerate Systems and Correlation Effects (1955) (772)
A Note on the Quantum‐Mechanical Perturbation Theory (1951) (643)
On the Nonorthogonality Problem (1970) (601)
Proton Tunneling in DNA and its Biological Implications (1963) (497)
Studies in Perturbation Theory. IV. Solution of Eigenvalue Problem by Projection Operator Formalism (1962) (496)
Quantum Theory of Atoms, Molecules and the Solid State: A Tribute to John C. Slater (1967) (477)
NATURAL ORBITALS IN THE QUANTUM THEORY OF TWO-ELECTRON SYSTEMS (1956) (447)
Scaling problem, virial theorem, and connected relations in quantum mechanics (1959) (380)
QUANTUM GENETICS AND THE APERIODIC SOLID. SOME ASPECTS ON THE BIOLOGICAL PROBLEMS OF HEREDITY, MUTATIONS, AGEING, AND TUMORS IN VIEW OF THE QUANTUM THEORY OF THE DNA MOLECULE (1966) (321)
STUDIES IN PERTURBATION THEORY. X. LOWER BOUNDS TO ENERGY EIGENVALUES IN PERTURBATION-THEORY GROUND STATE (1964) (313)
Quantum Theory of Many-Particle Systems. II. Study of the Ordinary Hartree-Fock Approximation (1955) (309)
Studies in perturbation theory . Part I. An elementary iteration-variation procedure for solving the Schrödinger equation by partitioning technique (1964) (294)
New Horizons of Quantum Chemistry (1983) (266)
Superposition of Configurations and Natural Spin Orbitals. Applications to the He Problem (1959) (245)
Quantum theory of cohesive properties of solids (2001) (238)
QUANTUM THEORY OF MANY-PARTICLE SYSTEMS. (1969) (238)
Angular Momentum Wavefunctions Constructed by Projector Operators (1964) (225)
Band Theory, Valence Bond, and Tight‐Binding Calculations (1962) (204)
Studies in perturbation theory XIII. Treatment of constants of motion in resolvent method, partitioning technique, and perturbation theory (1968) (175)
Approximate Formulas for Many‐Center Integrals in the Theory of Molecules and Crystals (1953) (156)
Correlation Problem in Many‐Electron Quantum Mechanics I. Review of Different Approaches and Discussion of Some Current Ideas (2007) (145)
Studies in Perturbation Theory. V. Some Aspects on the Exact Self‐Consistent Field Theory (1962) (144)
Correlation Splitting in Helium‐Like Ions (1956) (119)
Role of the Continuum in Superposition of Configurations (1955) (118)
Studies on the Alternant Molecular Orbital Method. I. General Energy Expression for an Alternant System with Closed‐Shell Structure (1962) (116)
Quantum systems in chemistry and physics (1999) (114)
THE NORMAL CONSTANTS OF MOTION IN QUANTUM MECHANICS TREATED BY PROJECTION TECHNIQUE (1962) (113)
SOME COMMENTS ON THE TIME-DEPENDENT VARIATION PRINCIPLE. (1972) (113)
Studies in perturbation theory. XI - Lower bounds to energy eigenvalues, ground state, and excited states. (1965) (111)
Studies of Atomic Self-Consistent Fields. I. Calculation of Slater Functions (1953) (108)
Expansion Theorems for the Total Wave Function and Extended Hartree-Fock Schemes (1960) (93)
A simple method of treating atomic integrals containing functions of r12 (1962) (90)
A simple method of treating atomic integrals containing functions of r12 (1962) (90)
Exchange, Correlation, and Spin Effects in Molecular and Solid-State Theory (1962) (87)
Studies in perturbation theory . II. Generalization of the Brillouin-Wigner formalism III. Solution of the Schrödinger equation under a variation of a parameter (1964) (79)
Note on the Separability Theorem for Electron Pairs (1961) (79)
Studies in perturbation theory: Part VI. Contraction of secular equations (1964) (76)
Partitioning technique, perturbation theory, and rational approximations (1982) (70)
Studies in perturbation theory: Part VIII. Separation of Dirac equation and study of the spin-orbit coupling and Fermi contact terms☆ (1964) (60)
VIRIAL THEOREM AND COHESIVE ENERGIES OF SOLIDS, PARTICULARLY IONIC CRYSTALS (1962) (59)
Linear algebra for quantum theory (1998) (56)
Variation Theorem for Excited States (1958) (55)
The historical development of the electron correlation problem (1995) (53)
Present Situation of Quantum Chemistry (1957) (52)
Some Studies of the General Hartree-Fock Method (1992) (50)
Quantum Theory of Electronic Structure of Molecules (1960) (49)
On the Change of Spectra Associated with Unbounded Similarity Transformations of a Many-Particle Hamiltonian and the Occurrence of Resonance States in the Method of Complex Scaling. Part I. General Theory (1988) (48)
STUDIES IN PERTURBATION THEORY. PART VII. LOCALIZED PERTURBATION (1964) (46)
Long-range interaction of two 1s-hydrogen atoms expressed in terms of natural spin-orbitals (1959) (45)
On the axioms of quantum theory formulated as a trace algebra (1982) (41)
Studies of Atomic Self-Consistent Fields. II. Interpolation Problems (1954) (40)
On the Calculation of the Inverse of the Overlap Matrix in Cyclic Systems (1960) (38)
Studies of Atomic Self-Consistent Fields. Analytic Wave Functions for the Argon-Like Ions and for the First Row of the Transition Metals (1956) (38)
Quantum Theory of Time-Dependent Phenomena Treated by the Evolution Operator Technique (1967) (37)
Studies on the Alternant Molecular Orbital Method. II. Application to Cyclic Systems (1962) (36)
Molecular orbitals in chemistry, physics, and biology : a tribute to R. S. Mulliken (1964) (34)
On the Molecular‐Orbital Theory of Conjugated Organic Compounds with Application to the Perturbed Benzene Ring (1953) (33)
Introduction to Part I (2001) (33)
Natural Spin Orbitals for Helium (1955) (32)
On the stability problem of a pair of adjoint operators (1983) (32)
Isotope effect in tunneling and its influence on mutation rates. (1965) (29)
Simple derivation of conditions for instability in the Hartree–Fock and projected Hartree–Fock schemes† (1981) (29)
On the Quantum‐Mechanical Calculation of the Cohesive Energy of Molecules and Crystals. Part I. A General Energy Formula for the Ground State (1951) (27)
Some Aspects on the Hamiltonian and Liouvillian Formalism, the Special Propagator Methods, and the Equation of Motion Approach (1985) (27)
Some comments on the periodic system of the elements (2009) (25)
Studies on proton transfers in water clusters and DNA base pairs (1987) (25)
A theoretical investigation into some properties of ionic crystals : a quantum mechanical treatment of the cohesive energy, the interionic distance, the elastic constants, and the compression at high pressures with numerical applications to some alkali halides (1948) (24)
On the Change of Spectra Associated with Unbounded Similarity Transformations of A Many-Particle Hamiltonian and the Occurrence of Resonance States in the Method of Complex Scaling. Part II. Applications to the Hartree-Fock Scheme Based on the Bi-Variational Principle (1989) (22)
Some Aspects on the Correlation Problem and Possible Extensions of the Independent-Particle Model (2007) (22)
The Mathematical Definition of a Molecule and Molecular Structure (1988) (22)
On nuclear motion and the definition of molecular structure (1991) (21)
On the historical development of the valence bond method and the non-orthogonality problem (1991) (21)
Calculation of Electric Dipole Moments of Some Heterocyclics (1951) (20)
On the state of the art of quantum chemistry (1986) (20)
SOME ASPECTS OF THE HYDROGEN BOND IN MOLECULAR BIOLOGY (1969) (20)
Twenty-five years of Sanibel symposia: A brief historic and scientific survey (2009) (18)
WAVE AND REACTION OPERATORS IN THE QUANTUM THEORY OF MANY-PARTICLE SYSTEMS (1963) (18)
On the Quantum‐Mechanical Calculation of the Cohesive Energy of Molecules and Crystals. Part II. Treatment of the Alkali Metals with Numerical Applications to Sodium (1951) (18)
Some Aspects on the Development of the Theory of Reduced Density Matrices and the Representability Problem (1987) (17)
Combined Use of the Methods of Superposition of Configurations and Correlation Factor on the Ground States of the Helium-Like Ions (1959) (17)
Some properties of inner projections (2009) (17)
A generalization of Brillouin's theorem and the stability conditions in the quantum-mechanical variation principle in the case of general trial wave functions (1986) (16)
Some remarks on the resemblance theorems associated with various orthonormalization procedures (1993) (16)
Approximate calculation of lifetimes of resonance states in the continuum from real stabilization graphs (1985) (15)
Some comments on the general Hartree—Fock method (1993) (15)
Quantum science : methods and structure : a tribute to Per-Olov Löwdin (1976) (15)
On the Hartree-Fock scheme for a pair of adjoint operators (1983) (14)
On Linear Algebra, the Least Square Method, and the Search for Linear Relations by Regression Analysis in Quantum Chemistry and Other Sciences (1992) (14)
Introductory Remarks to Nobel Symposium on Many-Body Theory of Atomic Systems (1980) (14)
Some comments on the construction of an orthonormal set of LCAO basis functions for crystals (1973) (13)
On the long way from the Coulombic Hamiltonian to the electronic structure of molecules (1989) (13)
Molecular Structure Calculations (1980) (12)
On the numerical integration of ordinary differential equations of the first order (1952) (10)
Some Aspects on the History of Computational Quantum Chemistry in view of the Development of the Supercomputers and Large-Scale Parallel Computers (1986) (10)
The calculation of upper and lower bounds of energy eigenvalues in perturbation theory by means of partitioning techniques. (1966) (10)
Theory of the interaction of swift ions with matter (2004) (10)
Electron gas test for the alternant molecular orbital method (1973) (10)
On the Sanibel coefficients in the expansion of spin-projected slater determinants (1983) (10)
Comments on the Analysis of Atomic Correlation Energies (1970) (10)
Food, ritual, and society : a study of social structure and food symbolism among the Newars (1998) (10)
Some properties of the bivariational Hartree–Fock scheme for complex symmetric many‐particle operators (1989) (9)
Food ritual and society among the Newars (1985) (8)
Connection between semi‐empirical and ab initio methods in the quantum theory of molecular electronic spectra (1999) (8)
Selected scientific papers of Egil A. Hylleraas. Edited by: John Midtdal, Harald Wergeland, and Knut Thalberg. Published by: NTH Press, Trondheim, Norway, 1968. Price: $27 for both volumes (1969) (8)
On operators, superoperators, hamiltonians, and liouvillians (2009) (8)
Some Aspects of the Biological Problems of Heredity, Mutations, Aging, and Tumours in View of the Quantum Theory of the DNA Molecule (2007) (7)
Some aspects of objectivity and reality in modern science (1992) (7)
Some aspects on the relation between the natural sciences and the human mind: An introduction to a panel discussion on the “origin of life and mind”† (1984) (7)
Studies in perturbation theory. XIV. Treatment of constants of motion, degeneracies and symmetry properties by means of multidimensional partitioning (2009) (6)
Concepts of convergence in mathematical chemistry (1990) (6)
The exchange phenomenon, the symmetric group, and the spin degeneracy problem (2009) (6)
Molecular Associations in Biology—a Brief Summary (1968) (6)
On the importance of theory in the future development of chemistry (1991) (6)
The projection operator for a space spanned by a linearly dependent set (1969) (6)
Quantum-mechanical kinetic energy transformation (1958) (6)
Nature of quantum chemistry (1967) (5)
Treatment of constants of motion in the variation principle. Symmetry properties of variational wavefunctions (1972) (5)
On some thermodynamical inequalities (1988) (5)
Some Comments On The Foundations Of Physics (1998) (5)
Some remarks on the perturbation and variation-perturbation calculations of the free energy for quantum systems (1989) (4)
Upper and lower bounds in second‐order perturbation theory and the unsÖld approximation (2009) (4)
Some Aspects on the Bloch-Lindgren Equation and A Comparison with the Partitioning Technique (1998) (4)
On boolean algebra and its importance for the computer sciences (1992) (4)
Some remarks on certain magnetic properties of water in the study of cancer (1987) (4)
Some current problems in quantum chemistry as described by their key words and the International Journal of Quantum Chemistry (1991) (4)
Density functional theory: Editorial (1982) (4)
Some current models of carcinogenesis (2009) (4)
On the pairing theorem and its extension (1991) (4)
On the Connection Between the Resolvent Methods and Partitioning Technique, Rational Approximations, and Perturbation Theory (1985) (4)
Remarks about the wave‐function representability of the first‐order reduced density matrices (1986) (3)
Introduction to a paper symposium on “the role of Quantum Chemistry as a foundation for the principles of chemistry” (1994) (3)
Addendum to “Quantum theory as a trace algebra” (1981) (3)
Comments on some models of carcinogenesis (2009) (3)
Some current problems in theoretical chemical physics to be solved (1994) (3)
To reach for the unreachable - psi and gamma (1988) (3)
New horizons of quantum chemistry : proceedings of the Fourth International Congress of Quantum Chemistry, held at Uppsala, Sweden, June 14-19, 1982 (1983) (3)
Some remarks on propagators and resolvents (1994) (2)
Mathematics in chemistry and in mathematical chemistry (1990) (2)
International Journal of Quantum Chemistry. Quantum Chemistry Symposium Number 27: Proceedings of the International Symposium on Atomic, Molecular, and Condensed Matter Theory and Computational Methods Held in St. Augustine, Florida on 13-20 March 1993 (1993) (2)
Some comments on the method of complex scaling to find physical resonance states (1986) (2)
Advances in Quantum Chemistry (1964) (2)
In memory of Jean‐Louis Calais (1996) (2)
Some remarks on the projector associated with the intersection of two linear manifolds (1981) (2)
Manifestations of vibronic coupling in chemistry and physics (2003) (2)
On the long way from the Coulombic Hamiltonian to the intermolecular energy surfaces: Concluding remarks at the tromsø conference, June 20–22, 1989 (1990) (2)
Det dukade bordet : Om partierna och de ekonomiska kriserna : [on the parties and the economic crises] (1998) (2)
International journal of quantum chemistry—a journal devoted to quantum theory and computations in chemistry, condensed matter physics, and biology. Editorial—program and policies (1992) (2)
DV-Xα for atomic spectroscopy and materials science (2001) (2)
Some Properties of Linear Functionals and Adjoint Operators. (1996) (2)
On rotations as special cases of unitary transformations with some applications to the theory of spin (1992) (2)
From electronic structure to time-dependent processes : a volume in honor of Giuseppe Del Re (2000) (1)
Call for contributions to paper symposium on semi‐empirical methods in quantum chemistry and solid‐state theory (1991) (1)
New perspectives in quantum systems in chemistry and physics (2001) (1)
Advances in quantum molecular sciences—a tribute to Kenichi Fukui (1983) (1)
ON FUNDAMENTALS, LOGIC, AND THE CONNECTION BETWEEN THE NATURAL-SCIENCES (1995) (1)
The calculation of atomic structures: D.R. Hartree: John Wiley & Son, New York, and Chapman & Hall, London, 1957. XIII + 181 pp., $5.00 (1958) (1)
Quantization as an Eigenvalue Problem for a Classical Wave in a Relativistic Framework (1998) (1)
SOME COMMENTS ON THE PROPERTIES OF UNITARY TRANSFORMATIONS ON LINEAR SPACES HAVING AN INDEFINITE METRIC AND THE CONNECTION WITH THE THEORY OF SPIN (1996) (1)
Proceedings of the International Symposium on Atomic, Molecular and Solid-state Theory, and Computational Quantum Chemistry Held at Flagler Beach, Florida, March 1-15, 1984 (1984) (1)
Proceedings of the International Symposium on Atomic, Molecular, and Solid-State Theory, held in honor of John C. Slater at Sanibel Island, Florida, January 16-21, 1967 (1967) (1)
Electronic energy of the DNA replication plane (2009) (1)
On the Origin of the Lorentz Transformations and the Special Theory of Relativity (1998) (1)
Some aspects on the development of the natural sciences and their importance for modern society and for our global environment (1997) (1)
DV-Xα for advanced nano materials and other interesting topics in materials science (2003) (1)
Some Recent Developments in the Quantum Theory of Many‐Electron Systems and the Correlation Problem (2007) (1)
The Importance of General Quantum Statistics and the Liouville Equation in Physical Chemistry - Some Recent Trends in Quantum Chemistry (1988) (1)
Calculation of lower bounds to energy eigenvalues by reduced density matrices and the representability problem (2009) (1)
[Quantum chemistry, cancer and aging]. (1977) (1)
Density Functional Theory (1982) (1)
The Size-Consistency Problem for Large Molecules (1980) (1)
Announcement of New Format (1988) (1)
On the present situation of quantum chemistry: Chairman's introductory remarks at the 6th ICQC† (1989) (1)
Applications of theoretical methods to atmospheric science (2008) (1)
Introduction to paper symposium on semiempirical methods in Quantum Chemistry and solid‐state theory (1992) (1)
PROCEEDINGS OF THE INTERNATIONAL SYMPOSIUM ON ATOMIC, MOLECULAR AND SOLID-STATE THEORY AND QUANTUM BIOLOGY HELD IN HONOR OF HENRY EYRING AT SANIBEL ISLAND, FLORIDA, JANUARY 13-18, 1969. PART 2. (1970) (0)
Proceedings of the International Symposium on Quantum Chemistry, Solid-State Theory, and Molecular Dynamics : held at St. Augustine, Florida, March 9-16, 1991 (1991) (0)
PROCEEDINGS OF THE INTERNATIONAL SYMPSOIUM ON ATOMIC, MOLECULAR AND SOLID-STATE THEORY AND QUANTUM BIOLOGY HELD IN HONOR OF HENRY EYRING AT SANIBEL ISLAND4 FLORIDA, JANUARY 13-18, 1969. PART 1. (1969) (0)
Erratum: The Importance of General Quantum Statistics and the Liouville Equation in Physical Chemistry - Some Recent Trends in Quantum Chemistry (1988) (0)
Proceedings of the International Symposium on Atomic, Molecular, and Condensed Matter Theory and Computational Methods, held at Ponce de Leon Resort, St. Augustine, Florida, February 25 - March 4, 1995 (1995) (0)
Eigenvalue problem in a linearly dependent basis and the super‐secular‐equation (2009) (0)
Proceedings ; International Symposium on Quantum Biology and Quantum Pharmacology Sanibei Island, 1974 (1974) (0)
Proceedings of the International Symposium on Atomic, Molecular and Solid-State Theory and Quantum Biology, held at Sanibel Island, Florida, 1971 (1971) (0)
Comments on Professor J. C. Slater's Paper "Cohesion in Monovalent Metals" (1966) (0)
Proceedings of the International Symposium on Atomic, Molecular, and Solid-state Theory, Collision Phenomena, and Computational Quantum Chemistry Held at Flagler Beach, Florida, March 3-12, 1983 (1983) (0)
Editorial comments: EDITORIAL COMMENTS (1983) (0)
Proceedings of the International Symposium on Atomic, Molecular, and Solid‐State Theory, Collision Phenomena, and Computational Methods (1979) (0)
Concluding remarks at the second watoc world congress in Toronto, July 8–14, 1991 (1991) (0)
Introduction to Part II (2009) (0)
Proceedings of the International Symposium on Quantum Chemistry, Solid-State Theory, and Molecular Dynamics, held at the Ponce de Leon Conference Center, St. Augustine, Florida, April 1-8, 1989 (1988) (0)
Proceedings of the International Symposium on Atomic, Molecular and Solid-State Theory, Scattering Problems, Many Body Phenomena, and Computational Quantum Chemistry Held in Marineland, Florida on March 18-23, 1985 (1985) (0)
DV-Xα for industrial-academic cooperation (2008) (0)
Linear algebra and the fundaments of quantum theory (1964) (0)
Proceedings of the International Symposium on Quantum Biology and Quantum Pharmacology : held at St. Augustine, Florida, March 17-24, 1990 (1990) (0)
Proceedings of the International Symposium on Quantum Chemistry, Solid-State Theory, and Computational Methods, held at Marineland, Florida, March 12-19, 1988 (1988) (0)
On the Origin of the De Broglie Relations and the Wave-Corpuscle Parallelism (1998) (0)
A Tribute to A. John Coleman — The “Tame” Mathematician (1987) (0)
Proceedings of the International Symposium on the Application of Fundamental Theory to Problems of Bilogy and Pharmacology, held at St. Augustine, Florida, March 14-21, 1992 (1992) (0)
Proceedings of the international symposium on quantum chemistry, solid-state theory, and molecular dynamics (1989) (0)
Proceedings of the International Symposium on Atomic, Molecular, and Condensed Matter Theory and Computational Methods, held at St. Augustine, Florida, March 14-21, 1992 (1992) (0)
Proceedings of the International Symposium on Quantum Chemistry, Solid-State Physics, and Computational Methods, held at Augustine, Florida, March 17-24, 1990 (1990) (0)
Proceedings of the International Symposium on Quantum Biology and Quantum Pharmacology : held at Palm Coast, Florida, March 12-5, 1984 (1984) (0)
SOME RECENT PROGRESS IN THE QUANTUM THEORY OF MANY-ELECTRON SYSTEMS (1962) (0)
Some comments on the treatment of symmetry properties in perturbation theory (2009) (0)
Propagating insight : a tribute to Yngve Öhrn (1999) (0)
Electronic Mobility and Transfer of Energy and Momentum as Time-Dependent Processes (1973) (0)
Meeting report (1986) (0)
Proceedings of the International Symposium on Atomic, Molecular and Solid-State Theory and Quantum Biology, held at Sanibel Island, Florida, January 15-20, 1968 (1968) (0)
A tribute to the life and work of Per-Olov Löwdin (2002) (0)
Proceedings of the International Symposium on Atomic, Molecular and Solid-State Theory, Collision Phenomena, and Computational Quantum Chemistry (17th), Held at Flagler Beach, Florida on 3-12 March 1983, (1983) (0)
On some properties of general linear operators (1993) (0)
The Kepler Problem in the Special Theory of Relativity with some Applications to the Hulse-Taylor's Binary Pulsar (1998) (0)
On operator inequalities as tools in quantum theory (1993) (0)
Proceedings of the International Symposium on Atomic, Molecular, and Solid-State Theory, Collision Phenomena, and Computational Methods, held at Flagler Beach, Florida, March 12-18, 1978 (1978) (0)
Proceedings of the International Symposium on Atomic, Molecular, and Condensed Matter Theory and Computational Methods, held at Ponte Vedra Beach, Florida, February 12-19, 1994 (1994) (0)
Proceedings of the International Symposium on Atomic, Molecular, and Condensed Matter Theory and Computational Methods, held at St. Augustine, Florida, March 13-20, 1993 (1993) (0)
Chemical physics of surfaces, catalysis and membranes (1977) (0)

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